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tekmarNet2 House Control 402
D 40209/10
HVAC Systems Replaces: 01/1
Installation & Operation Manual
Menu
House Control 402
Item
VIEW
Boil Exp Boil SystemZones1 2 3 4
Calls Pumps
BenefitsEnergy efficiency through Outdoor Temperature
Reset with Indoor Feedback
Indoor Feedback minimizes the water temperature
(increasing energy savings), and the efficiency ofyour mechanical equipment through integrated
tekmarNetThermostatsZone Synchronization reduces equipment cycling
Auto Differential - Reduces boiler cycling
Compact enclosure for flexible installation
Simple zone expansion using Wiring Centers
The House Control 402 is designed to operate as part of acomplete hydronic heating system with tekmarNet2 (tN2)thermostats. It can provide operation of two outdoor reset
water temperatures such as radiant floor heating on the firsttemperature and baseboard or fan coil heating on the secondtemperature. In addition the control has Domestic Hot Waterand Setpoint capabilities. It is easy to add more zones, addschedules or other convenient accessories through the useof the tekmarNet4 (tN4) Expansion terminals.
FeaturesSingle on-off, two-stage or modulating boiler
Boiler outdoor reset temperature
Mixing outdoor reset temperature
Domestic Hot Water tank operation
Setpoint operation
Mix with variable speed injection, floating action,
or proportional 0-10 V (dc), proportional 4-20 mAFor use with tekmarNet2 Thermostats
Four 24 V (ac) powered zone valve outputs
Expand to 24 zones per temperature usingtekmarNet4 expansion ports
CSA C US Certified for use in USA and Canada
Introduction
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Table of Contents
Getting Started
Caution
Installation ......................................................................2
Preparation ................................................................ 2Physical Dimensions ................................................. 3Installation Location .................................................. 3
Rough-In Wiring ........................................................ 3Sizing the Transformer .............................................. 4
Control Wiring ........................................................... 4
Sensor Wiring ............................................................ 7Testing the Sensor Wiring ......................................... 9Testing the Control Wiring ......................................... 9Max Heat ..................................................................10
Applications .................................................................. 11
User Interface ...............................................................13
Display......................................................................13Symbols ...................................................................13
Navigating The Display ............................................14Access Levels and Thermostat Lock ........................14Programming and Settings .......................................14
View Menu ...............................................................15
Adjust Menu ........................................................16-18
Monitor Menu ...........................................................19Toolbox Menu .......................................................... 20
Sequence of Operation ................................................21
tekmarNetSystem ..................................................21Mix Temperature Reset Operation ...........................21Boiler Temperature Reset Operation ....................... 22
Domestic Hot Water Tank Operation ....................... 23
Setpoint Operation .................................................. 25Boiler Operation ...................................................... 25Domestic Hot Water Heat Source ............................27
Pump Operation .......................................................27Energy Saving Features .......................................... 28
Troubleshooting ............................................................28
Error Messages .................................................. 28-30
Frequently Asked Questions .............................. 30-31Job Record ...............................................................31
Technical Data ..............................................................32
Limited Warranty and Product Return Procedure ........32
Congratulations on the purchase of your new tekmarNetHouse Control!
This manual covers the complete installation, programming and sequence of operation for this control. You will also findinstruction on testing, commissioning, and troubleshooting the control and system that it operates.
Improper installation and operation of this control couldresult in damage to the equipment and possibly evenpersonal injury or death. It is your responsibility to ensure
that this control is safely installed according to all applicablecodes and standards. This electronic control is not intendedfor use as a primary limit control. Other controls that areintended and certified as safety limits must be placed into
the control circuit. Do not attempt to service the control.Refer to qualified personnel for servicing. There are nouser serviceable parts. Attempting to do so voids warrantyand could result in damage to the equipment and possiblyeven personal injury or death.
Installation
The installer must ensure that this control and its wiring areisolated and/or shielded from strong sources of electromagneticnoise. Conversely, this Class B digital apparatus complies
with Part 15 of the FCC Rules and meets all requirements ofthe Canadian Interference-Causing Equipment Regulations.However, if this control does cause harmful interferenceto radio or television reception, which is determined byturning the control off and on, the user is encouraged to try
to correct the interference by re-orientating or relocatingthe receiving antenna, relocating the receiver with respectto this control, and/or connecting the control to a different
circuit from that to which the receiver is connected.
Cet appareil numrique de la classe B respecte toutesles exigences du Rglement sur le matriel brouilleur duCanada.
Radio Frequency Interference
Preparation
Tools Required ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------tekmar or jeweller screwdriver
Phillips head screwdriver
Needle-nose Pliers
Wire Stripper
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Materials Required ----------------------------------------------------------------------------------------------------------------------------------------------------------------------(2) #10 x 1 Wood Screws
(3) Wire Nuts
18 AWG LVT Solid Wire (Low Voltage Connections)
14 AWG Solid Wire (Line Voltage Connections)
tekmar 009K (24 V (ac) transformer with 4 x 4 junction box
Cable or Conduit Connectors
Power Required ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------120 V (ac), 1-phase, 15 A service from circuit breaker
panel
Power disconnect (optional)
Installation Location
When choosing the location for the control, consider thefollowing:
Keep dry. Avoid potential leakage onto the control.RH 90% to 104F (40C).
Non-condensing environment.
Do not expose to operating temperatures beyond 32-
104F (0-40C)
Provide adequate ventilation.
Keep away from equipment, appliances or other
sources of electrical interference.
Locate the control near pumps and/or zone valves ifpossible.
Provide easy access for wiring, viewing and adjustingthe control.
Mount approximately 5 ft. (1.5 m) off the finished floor.
Install the electrical junction box to a wall using #10x 1 wood screws. Wall anchors are recommended
when mounting to sheet rock wallboard or masonry.
Rough-In Wiring
Line Voltage Wiring----------------------------------------------------------------------------------------------------------------------------------------------------------------------The control operates a number of pumps through wiringon the back of the control. The control must be mountedto a 4 x 4 electrical junction box so that these electricalconnections are safely contained.
For ease of service, the circuit breaker or power disconnectshould be located in reasonably close proximity to theequipment.
All line voltage wire connections are recommended tobe pulled inside a flexible or solid conduit. Always followproper wiring practices, building and electrical codes foryour jurisdiction.
Each cable must be pulled from the equipment to theelectrical junction box. It is recommended to label eachcable for easy identification. All line voltage wires shouldbe stripped to a length of 1/2 (13 mm).
Pull a three conductor 14 AWG cable for the following
equipment:
Circuit Breaker or Power Disconnect
Mix System Pump
Boiler System Pump
DHW Tank Pump (if applicable)
Variable Speed Injection Pump (if applicable)
Physical Dimensions
Side ViewCover Off Front View Back View
51/2(140 mm)
51/2(140 mm)
Menu
House Control 402
Item
+
Mix
Com
Boil
Out
DHW
VlvC VlvC VlvCZone3Zone 1 Zone 2 Zone 4
MadeinCanada
VlvC
Com
Zone1
H8007B
Z on e 2 Z on e 3 Z on e 4t N2 t N2 t N2 t N2 t N2 t N2 t N2 t N2 C
FloatingActionClsOpn
Sensors-NoPower
Call
Call
tN4
tN4
C
C
Moddc/mA
BoilExp.
MixExp.
Setpoint
DHW
Useat least 167F(75C)conductorsRC
Input Power
Stage2
Stage1
11/8(30 mm)
7/8(22 mm)
CL
1/2 Knock-out (x 4)
Control designed to mount on 4 x 4electrical box (not included).
Electrical box shown comes with 009K
21/4(57 mm)
21/4(57 mm)
BoilS
ystemP
um
p
Mix
SystemP
um
p
DHWP
um
p
Varia
ble
SpeedP
um
p
Pum
pP
ow
erL
7/8 x 1/2 (23 mm x 12 mm)Knock-out (x 4)
1/2 x 5/8(12 mm x 16 mm)Knock-out (x 4)
1/8(3 mm)
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The control requires an external transformer. A tekmarTransformer 009 (or 009K which includes a 4x 4 electricalbox) can supply up to 40 VA, and includes an in-line fuse
to protect the transformer and control.
In order to correctly size the external transformer, all loadsconnected to the control must be taken into account.
When adding up the loads, consider the following:
tekmarNet2 Thermostats draw approximately 2 VA each.
Each zone valve must be sized for peak load. This canbe obtained by multiplying the peak current draw (inAmps) by 24 V (ac).
If using a Floating Action mixing valve, add the VAdraw for the actuating motor. A tekmar Actuating Motor741 draws 1.5 VA during normal operation.
The total power capacity of the power supply should belarger than the total load of all the devices connectedto the control. This total load must not exceed 100 VA.Multiple tekmar Transformer 009s can be wired togetherto increase total VA capacity.
The following chart is provided to simplify transformersizing:
Zone 1 2 3 4
Thermostat Load
Zone Valve LoadFloating
Action (VA)Control
Load (VA)
Total Zone Load + + + + + 2
Transformermust exceed:
VA
Sizing the Transformer
Control Wiring
Line Voltage Wiring----------------------------------------------------------------------------------------------------------------------------------------------------------------------Ground the Pumps
Connect the pump grounds to the power supplyground as shown in Figure 1. The ground wire mustalso be grounded to the electrical box.
Wire the Pump Neutrals
Connect the Neutral (N) wires from each pump and wireto the 115 V (ac) Neutral (N) wire. If the transformer has
been mounted to this electrical box, connect its neutralwire with this group. This is shown in Figure 2.
Wire the Pump Power (L)Connect the 115 V (ac) line voltage (L) wire to the redPump Power (L) wire on the back of the House Controland to the 115 V (ac) side of the transformer. Use a
wire nut or approved connector. See Figure 3.
Wire the Pumps
Wire each remaining line voltage pump wire into the
push-in wire connector of the corresponding pumplead on the back of the House Control. This is shownin Figure 4.
CAUTION: TURN ALL POWER OFF BEFORE PERFORMING ANY WIRING.
Each cable must be pulled from the equipment to thecontrols plastic enclosure. All low voltage wiring connectionsenter the enclosure through conduit knockouts on thesides, or through the square knockouts on the rear. It isrecommended to label each cable for easy identification.
All low voltage wires are to be stripped to a length of 3/8(9 mm) to ensure proper connection to the control.
Pull two conductor 18 AWG LVT cable, up to 500 feet
(150 m) for the following equipment:tekmarNet2 Thermostats
Zone Valves
Mixing Valve Actuator Proportional 0-10 V (dc)
Boiler Stage 1 T-T
Boiler Stage 2 T-T (if applicable)
Modulating Boiler 0-10 V (dc) or 4-20 mA (if applicable)
Outdoor Temperature Sensor
Boiler Supply Temperature Sensor
Mix Supply Temperature Sensor
DHW Tank Temperature Sensor (if applicable)
DHW Tank Aquastat (if applicable)
Setpoint Devices (if applicable)
Pull three conductor 18 AWG LVT cable for the following
equipment:
Mixing Valve Actuator Floating Action
tekmarNet4 Accessories (User Switch, Timer)
Low Voltage Wiring----------------------------------------------------------------------------------------------------------------------------------------------------------------------
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DHW Pump
Mix SystemPump
PowerSource(L,N)
V. S. Pump
Boil Sys PumpBoil SystemPump
Mix SystemPump
DHWPump
VariableSpeedPump
PumpPower L
402
Strip wires1/2 inch (13 mm).Installed wires arenot removable.12-18 AWG
Variable Speed Pump
DHW Pump
Boil System Pump
Mix SystemPump
Power Source(L,N)
Pump
Pump
Pump
Pump
Variable Speed Pump
DHW Pump
Boil System Pump
Mix SystemPump
Power Source(L,N)
Pump
Pump
Pump
Pump
Figure 1 - ConnectGround Wires
Boil SystemPump
Mix SystemPump
DHWPump
VariableSpeed Pump
Pump Power L
402
Strip wires1/2 inch(13 mm).Installed wires arenot removable.12-18 AWG
V. S. Pump
DHW Pump
Boil Sys Pump
Mix SystemPump
PowerSource(L,N)
Figure 2 - ConnectNeutral Wires
Figure 3 - ConnectLine Voltage (Hot)
Figure 4 - ConnectPump Line (Hot)
Mix
Boil
DHW
VariableSpeed
115 V (ac)
NL G
to pump grounds
N
L
Back of House Control 402
Strip wires
1/2 inch (13 mm).Installed wires arenot removable.12-18 AWG
(blue)
(red)
(black)
(black)
(black)
Boil System Pump
Mix System Pump
DHW Pump
VariableSpeed Pump
Pump Power L
Rear Line Voltage Wiring Diagram--------------------------------------------------------------------------------------------------------------------------------------
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External Power Supply
It is strongly recommended that a transformer with an in-linefuse be used in order to protect the transformer from highcurrents. The tekmar Transformer 009 includes a fuse.
Connect the 24 V (ac) leads from the transformer to the
C and R terminals marked Input Power on the 402.
tN2 Thermostats
The 402 is designed to operate with tekmarNet2 Thermostats.They provide the heating and cooling control for each zone,and communicate with any other tekmarNet device onthe system.
Connect the tN2 terminals from each thermostat to thecorresponding tN2 terminals for each zone on the 402.
Zone Valves
Wire the zone valves to the C and Vlv terminals on the402.
End switches on zone valves are not required whenusing the 402.
tN4 Expansion Terminals
The 402 uses the Expansion tN4 and C terminals tocommunicate with additional thermostats, setpoint controls,and other tekmarNetdevices. There are two sets of tN4and C terminals on the 402.
Boil Exp.
To add additional boiler water temperature zones (typicallybaseboard or fan coil zones) to the system, install atekmarNetWiring Center.
Connect the tN4 and C Boil Exp. terminals on the 402to the corresponding tN4 and C Expansion terminalson the external Wiring Center.
Mix Exp.The 402 has the capacity to expand the number of mixingzones in the system beyond the four on board zones. To
add additional mix water temperature zones (typicallyradiant floor zones) to the system, install a tekmarNet
Wiring Center.
Connect the tN4 and C Mix Exp. terminals on the 402to the corresponding tN4 and C Expansion terminals
on the external Wiring Center.
Low Voltage Wiring----------------------------------------------------------------------------------------------------------------------------------------------------------------------
Ensure that the pump wires are neatly tucked insidethe electrical box.
Using 2 of the 4 holes in the back of the enclosure, se-curely fasten it to the electrical junction box with 2 #10
screws as shown in Figure 5.
Install The Enclosure------------------------------------------------------------------------------------------------------------------------------------------------------------------Figure 5
Domestic Hot Water (DHW) or Setpoint Call
When the control receives a DHW Call or Setpoint Call forheat it will override Outdoor Reset and Indoor Feedback
and operate the boiler to heat the DHW tank or the Setpointequipment.
To create a DHW call, wire a dry contact OR apply 24V (ac) to the DHW call terminals.
To create a Setpoint call, wire a dry contact OR apply24 V (ac) to the Setpoint call terminals.
Wiring the Boiler
The 402 can operate a single modulating boiler, singleon-off, or a single two-stage on-off boiler.
On/Off Boiler
Connect the Boiler Stage 1 terminals on the 402 to the
T-T (or R-W) terminals on the boiler.
If required, connect the Boiler Stage 2 terminals on the402 to the second stage T-T (or R-W) terminals on theboiler.
Modulating Boiler
Wire the Mod (dc/mA) positive (+) and negative (-) ter-minals on the 402 to the input signal terminals on the
boiler. Correct polarity of the wires is important.
In some cases, the modulating boiler also requires
contact closure on the T-T terminals to fire the boiler. Ifrequired, connect the Boiler Stage 1 terminals on the
402 to the T-T (or R-W) terminals on the boiler.
Floating Action Terminals
Applications that use a floating action mixing valve actuator(tekmar type 741) will use the Floating Action Opn, Cls, andC terminals. This is a powered output (24 V (ac)).
Wire the Opn, Cls, and C terminals on the 402 to the
open, close, and C terminals on the floating actionactuator.
Proportional Mixing (0-10 V (dc) or 4-20 mA)
Applications that use a proportional mixing valve actuatorwill use the Mod (dc/mA) terminals. Proportional mixing canonly be used when a modulating boiler is not installed.
Wire the Mod positive (+) on the 402 to the positive (+)
terminal on the actuator.
Wire the Mod negative (-) on the 402 to the negative (-)
or common terminal on the actuator.
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R
C
L
N
Com
Open
Close
ExpansiontN4 Boil
C
tN4
ModulatingBoiler
+
ExpansiontN4 Mix
C
tN4
2
1
Menu
House Control 402
Item
+
Mix
Com
BoilOut
DHW
VlvC VlvC VlvC
Zone 3Zone 1 Zone 2 Zone 4
Made in Canada
VlvC
Com
Zone 1
H8007B
Zone 2 Zone 3 Zone 4tN2 tN2 tN2 tN2 tN2 tN2 tN2 tN2 C
Floating ActionClsOpn
Sensors-NoPower
Call
Call
tN4
tN4
C
C
Moddc/mA
BoilExp.
MixExp.
Setpoint
DHW
Use at least 167F
(75C) conductorsRC
Input Power
Stage2
Stage1
Zone Valves24 V (ac) Transformer 009
DHW Callfrom DHW
Tank Aquastat(optional)
Setpoint Call
OutdoorSensor
070
Mix SupplySensor 082
Boiler SupplySensor 082
DHW TankSensor 082
One or Two StageBoiler T-T
tekmarNet2 Thermostats
24 V (ac) FloatingAction Actuator
Front Low Voltage Wiring Diagram --------------------------------------------------------------------------------------------------------------------------------------
Sensor Wiring
Note: The temperature sensor (thermistor) is built into the070 enclosure.
Remove the screw and pull the front cover off thesensor enclosure.
The 070 can either be mounted directly onto a wall ora 2 x 4 electrical box. When the 070 is wall mounted,
the wiring should enter through the back or bottom ofthe enclosure. Do not mount the 070 with the conduit
knockout facing upwards as rain could enter the enclo-sure and damage the sensor.
In order to prevent heat transmitted through the wallfrom affecting the sensor reading, it may be necessary
to install an insulating barrier behind the enclosure.
The 070 should be mounted on a wall which best rep-
resents the heat load on the building (a northern wallfor most buildings and a southern facing wall for build-
ings with large south facing glass areas). The 070should not be exposed to heat sources such as venti-
lation or window openings.
The 070 should be installed at an elevation above
the ground that will prevent accidental damage ortampering.
Mounting the Outdoor Sensor 070----------------------------------------------------------------------------------------------------------------------------------------
Sensor with bottomentry wiring
Sensor with rearentry wiring
Sensor mountedonto 2" x 4"electrical box
tekmarNet4Expansion to
Wiring Centers,Timers, or
User Switch
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Connect 18 AWG or similar wire to the two terminalsprovided in the enclosure and run the wires from the
070 to the control. Do not run the wires parallel to tele-phone or power cables. If the sensor wires are located
in an area with strong sources of electromagnetic in-terference (EMI), shielded cable or twisted pair should
be used or the wires can be run in a grounded metalconduit. If using shielded cable, the shield wire should
be connected to the Com or Com Sen terminal on thecontrol and not to earth ground.
Follow the sensor testing instructions in this brochureand connect the wires to the control.
Replace the front cover of the sensor enclosure.
Wiring the Outdoor Sensor 070----------------------------------------------------------------------------------------------------------------------------------------------Wires from outdoor
sensor to control
terminals(Com Sen - Out Sen)
Sensor is built into
the enclosure
Mounting the Boiler and Mix Sensor 082 --------------------------------------------------------------------------------------------------------------------------Note: These sensors are designed to mount on a pipe orin a temperature immersion well.
The Universal Sensor should be placed downstream of apump or after an elbow or similar fitting. This is especially
important if large diameter pipes are used as the thermalstratification within the pipe can result in erroneous sensorreadings. Proper sensor location requires that the fluidis thoroughly mixed within the pipe before it reaches thesensor.
Strapped to Pipe
The Universal Sensor can be strapped directly to the pipeusing the cable tie provided. Insulation should be placed
around the sensor to reduce the effect of air currents onthe sensor measurement.
Immersion Well
If a Universal Sensor is mounted onto 1 (25 mm) diameterL type copper pipe, there is approximately an 8 seconddelay between a sudden change in water temperature andthe time the sensor measures the temperature change.This delay increases considerably when mild steel (black
iron) pipe is used. In general, it is recommended thata temperature well be used for steel pipe of diametergreater than 1-1/4 (32 mm). Temperature wells are alsorecommended when large diameter pipes are used andfluid stratification is present.
Conduit Connection
The Universal Sensor 082 and Universal Sensor Enclosure080 (sold separately) are specifically designed to mount
onto a 3/8 (10 mm) ID temperature well that is suppliedwith an end groove. To install the well, plumb a T into thepipe and fix the well into the T. The 080 enclosure hasa 7/8 (22 mm) back knockout that must be removed andfitted over the temperature well. The 082 is then insertedinto the well and the retaining clip supplied with theenclosure is snapped onto the well end groove. If the wellhas a threaded end, the installer must supply a standardthreaded conduit retaining ring. The two wires from thesensor are connected to the terminal block provided in theenclosure. The other side of the terminal block is used toconnect wires from the control.
Bottom ofEnclosure 080
UniversalSensor 082 Cable Tie
Sensor Well
Retaining Clip
UniversalSensor 082
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A good quality test meter capable of measuring up to 5,000k (1 k = 1000 ) is required to measure the sensorresistance. In addition to this, the actual temperature mustbe measured with either a good quality digital thermometer,or if a thermometer is not available, a second sensor canbe placed alongside the one to be tested and the readingscompared.
First measure the temperature using the thermometer andthen measure the resistance of the sensor at the control.The wires from the sensor must not be connected to thecontrol while the test is performed. Using the chart below,
estimate the temperature measured by the sensor. Thesensor and thermometer readings should be close. If thetest meter reads a very high resistance, there may be abroken wire, a poor wiring connection or a defective sensorIf the resistance is very low, the wiring may be shortedthere may be moisture in the sensor or the sensor maybe defective. To test for a defective sensor, measure theresistance directly at the sensor location.
Do not apply voltage to a sensor at any time as damage
to the sensor may result.
Testing the Sensor Wiring
Temperature Resistance Temperature Resistance Temperature Resistance Temperature Resistance
F C F C F C F C-50 -46 490,813 20 -7 46,218 90 32 7,334 160 71 1,689
-45 -43 405,710 25 -4 39,913 95 35 6,532 165 74 1,538
-40 -40 336,606 30 -1 34,558 100 38 5,828 170 77 1,403
-35 -37 280,279 35 2 29,996 105 41 5,210 175 79 1,281
-30 -34 234,196 40 4 26,099 110 43 4,665 180 82 1,172
-25 -32 196,358 45 7 22,763 115 46 4,184 185 85 1,073
-20 -29 165,180 50 10 19,900 120 49 3,760 190 88 983
-15 -26 139,402 55 13 17,436 125 52 3,383 195 91 903-10 -23 118,018 60 16 15,311 130 54 3,050 200 93 829
-5 -21 100,221 65 18 13,474 135 57 2,754 205 96 763
0 -18 85,362 70 21 11,883 140 60 2,490 210 99 703
5 -15 72,918 75 24 10,501 145 63 2,255 215 102 648
10 -12 62,465 80 27 9,299 150 66 2,045 220 104 598
15 -9 53,658 85 29 8,250 155 68 1,857 225 107 553
Testing the Control Wiring
Testing the Power ------------------------------------------------------------If the control display does not turn on, check the InputPower wiring terminals using an electrical multimeter.
The voltage should measure between 21.6 to 26.4 V
(ac). If the voltage is below this range, measure theline voltage side of the transformer. The voltage shouldmeasure between 103.5 to 126.5 V (ac).
Testing the Thermostats ----------------------------------------------If the thermostat display turns on, this indicates that
the thermostat is operating correctly and there are noelectrical issues. In the event that the display is off, or
the display is cycling on and off, follow this procedure.
1. Remove the tN2 wires from the thermostat.
2. Use an electrical meter to measure DC voltage betweenthe tN2 terminals.
If the DC voltage is 0 V (dc) for 20 seconds, then there isan open or short circuit in the tN2 wires. If the DC voltageis 0 V (dc) for 10 seconds and then is 23 to 24 V (dc) for 5seconds, this indicates the wiring is correct.
3. Connect the thermostat to the tN2 wires from a zoneon a House Control, Wiring Center, or Zone Manager.
4. If the thermostat display is off, or is cycling on and off,move the thermostat to the next available zone on theHouse Control, Wiring Center, or Zone Manager.
If the thermostat display remains permanently on, theremay be a fault with the previously tried zone on the HouseControl, Wiring Center, or Zone Manager.
If the thermostat display continues to be off, or is cyclingon and off, there may be a fault on the thermostat.
If a fault is suspected, contact your tekmar salesrepresentative for assistance.
User Test----------------------------------------------------------------------------The User Test is found in the Toolbox menu of the control.
Press the Menu button to access the Toolbox Menu. Pressthe Item button to locate the User Test.
Start the test sequence by going to the User Test item andpressing the Up arrow button.Pause the test sequence by pressing the Item button. Toadvance to the next step, press the Item button again.If the test sequence is paused for more than five minutes
the control exits the entire test routine and returns to normaoperation.
To advance to a particular step, repeatedly press and
release the Item button to display the appropriate device.User Test Sequence
Step 1 The Mix 1 device ramps up to 100% over 30 secondsor according to the motor speed setting.
Step 2 The Mix 1 device ramps down to 0% over 30 secondsor according to the motor speed setting.
Step 3 Zone 1 turns on for 10 seconds.
Step 4 Zone 2 turns on for 10 seconds.
Step 5 Zone 3 turns on for 10 seconds.
Step 6 Zone 4 turns on for 10 seconds.
Step 7 The mix system pump turns on for 10 seconds.
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Step 8 The DHW pump turns on for 10 seconds.
Step 9 The boiler system pump turns on for 10seconds.
Step 10 During the boiler test step, zone relays 1 through 4turn on, the mix system pump turns on, and the boilsystem pump turns on. The mixing device operatesup to 20%. This ensures there is a location for heatto move when the boiler is turned on.
If the Boil Type is 1 Stage, the boiler stage 1 relay is
closed for 10 seconds and then opened.If the Boil Type is 2 Stage, the boiler stage 1 relay isclosed for 10 seconds, then the boiler stage 2 relay is
closed for 10 seconds and then both relays are opened.
If Boiler Type is modulating 0 - 10, the boiler stage1 relay is closed for 10 seconds and the modulating
output operates at 50 % [5 V (dc)].
If Boiler Type is modulating 4 - 20, the boiler stage
1 relay is closed for 10 seconds and the modulatingoutput operates at 50 % (12 mA).
Step 11 Control returns to normal operation.
Testing the Variable Speed Injection Pump --------Activate the User Test sequence and pause at Step 1by pressing the Item button once the injection pump isoperating at 100%. Using an electrical meter, measure thevoltage between the variable speed pump and a neutral.The voltage should measure between 103.5 V (ac) and126.5 V (ac).
Testing the Zone Output --------------------------------------------Activate the User Test sequence and pause at Step 3 bypressing the Item button once Zone 1 turns on. Using anelectrical meter, measure the voltage between the zonevalve and the common (C) terminals. The voltage shouldmeasure between 21.6 V (ac) and 26.4 V (ac). Repeat for
Zones 2, 3, and 4.
Testing the Mix System Pump ----------------------------------Activate the User Test sequence and pause at Step 7 by
pressing the Item button once the mix system pump turnson. Using an electrical meter, measure the voltage betweenthe mix system pump and a neutral. The voltage shouldmeasure between 103.5 V (ac) and 126.5 V (ac).
Testing the DHW Pump ------------------------------------------------Activate the User Test sequence and pause at Step 8 by
pressing the Item button once the DHW pump turns on.Using an electrical meter, measure the voltage betweenthe DHW pump and a neutral. The voltage should
measure between 103.5 V (ac) and 126.5 V (ac).
Testing the Boiler System Pump------------------------------Activate the User Test sequence and pause at Step 9 bypressing the Item button once the boiler system pump turns
on. Using an electrical meter, measure the voltage betweenthe boiler system pump and a neutral. The voltage should
measure between 103.5 V (ac) and 126.5 V (ac).
Testing the Boiler Stage 1 Contact--------------------------Activate the User Test sequence and pause at Step 10 bypressing the Item button once the boiler stage 1 turns on.
Using an electrical meter, measure for continuity over theboiler stage 1 terminals.
Testing the Boiler Stage 2 Contact--------------------------This test applies for 2 stage on-off boilers only.Activate the User Test sequence and pause at Step 10 by
pressing the Item button once the boiler stage 2 turns on.Using an electrical meter, measure for continuity over the
boiler stage 2 terminals.
Testing the Boiler Modulating Output--------------------This test applies for modulating boilers only.
Active the User Test sequence and pause at Step 10 bypressing the Item button once the boiler stage 1 turns on.
Using an electrical meter, measure for either a 5 V (dc) or
12 mA signal. The Boil Type setting selects whether thesignal is V (dc) or mA.
Testing the DHW Call----------------------------------------------------Remove all wires from the DHW Call terminals. The control
display should show no DHW Call. Reconnect wires. Thenapply either a short circuit or 24 V (ac) over the DHW Callterminals. The control should now show a DHW Call.
Testing the Setpoint Call --------------------------------------------Remove all wires from the Setpoint Call terminals. Thecontrol display should show no Setpoint Call. Reconnectwires. Then apply either a short circuit or 24 V (ac) overthe Setpoint Call terminals. The control should now show
a Setpoint Call.
The control has a function called Max Heat. In this mode,the control turns on and operates the system up to themaximum set temperatures as long as there is a call forheat. Use this mode to run the circulators during systemstart-up and commissioning, purging air from the piping.This feature is useful when drying sheet rock and paint in
the building.
To enable Max Heat, enter the Toolbox Menu and find MaxHeat. Use the up arrow to select On.
When a space heating call is present, the boiler will
run to maintain a target of Boil Design + 10F (+ 6C).(One can purge the system using this test and leave
the boiler un-powered. This will prevent heat from en-tering the system during the purge.)
When a DHW Call or Setpoint Call is present, the
boiler will operate at the DHW exchange or Setpointtemperature settings.
WWSD and DHW Priority is disabled during Max Heatmode.
When Max Heat is on the display will show Max Heat
Test.
Max Heat will automatically turn off after 24 hours.
To Cancel Max Heat, go to Max Heat in the Toolbox menuand use the down arrow to select Off.
Max Heat
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Applications
Mix
Boil
DHW
VariableSpeed
(P4)
(P1)
(P3)
(P2)
115 V (ac)
NL G
to pump grounds
N
L
Back of House Control 402
Strip wires
1/2 inch (13 mm).
Installed wires are
not removable.
12-18 AWG
R
C
L
N
ExpansiontN4 Boil
C
tN4
ExpansiontN4 Mix
C
tN4
(blue)
(red)
(black)
(black)
(black)
1
Menu
House Control 402
Item
+
Mix
Com
Boil
Out
DHW
VlvC VlvC VlvCZone 3Zone 1 Zone 2 Zone 4
Made in Canada
VlvC
Com
Zone 1
H8007B
Zone 2 Zone 3 Zone 4tN2 tN2 tN2 tN2 tN2 tN2 tN2 tN2 C
Floating ActionClsOpn
Sen
sors-N
oP
ow
er
Call
Call
tN4
tN4
C
C
Moddc/mA
BoilExp.
MixExp.
Setpoin
t
DHW
Use at least 167F(75C) conductorsRC
Input Power
Stage2
Stage1
Boil System Pump
Mix System Pump
DHW Pump
VariableSpeed Pump
Pump Power L
Description: The House Control 402 operates an On/Off boiler with indirect Domestic Hot Water. Mixing is performed withvariable speed injection, which supplies an outdoor reset water temperature to the 4 onboard mix temperature hydroniczones. Additional zones (boiler or mix) can be added using the tN4 Expansion terminals.
Single Boiler, DHW Tank, Variable Speed Mixing, 4 Mix Zones A402-1
402070S3
S2S1
OutdoorSensor
(S3)
tekmarNet2 Thermostats
Boiler T-T
24 V (ac)Transformer 009
Mix Sensor (S2)
Boiler Sensor (S1)
DHW Call
Zone Valves (Z1 to Z4)
tekmarNet4Expansion to
Wiring Centers,Timers, or
User Switch
tekmarNet2 Thermostats
P1
P2
P3 P4
Z1 Z2 Z3 Z4
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Description: The House Control 402 operates a modulating boiler with indirect Domestic Hot Water. Mixing is performed witha three-way floating action mixing valve, which supplies a reset water temperature to four mix temperature hydronic zones.
Two boiler water temperature zones shown are operated by a Wiring Center through the tN4 Boil Expansion terminals.
Mix
Boil
DHW
(P3)
(P1)
(P2)
115 V (ac)
NL G
to pump grounds
L
Back of House Control 402
Strip wires1/2 inch (13 mm).Installed wires arenot removable.12-18 AWG
R
C
L
N
Com
Open
Close
ExpansiontN4 Boil
C
tN4
ModulatingBoiler
+
ExpansiontN4 Mix
C
tN4
(blue)
(red)
(black)
(black)
(black)
1
313
Menu
House Control 402
Item
+
Mix
Com
BoilOut
DHW
VlvC VlvC VlvC
Zone 3Zone 1 Zone 2 Zone 4
Made in Canada
VlvC
Com
Zone 1
H8007B
Zone 2 Zone 3 Zone 4tN2 tN2 tN2 tN2 tN2 tN2 tN2 tN2 C
Floating ActionClsOpn
Sensors-NoPower
Call
Call
tN4
tN4
C
C
Moddc/mA
BoilExp.
MixExp.
Se
tpoint
DHW
Use at least 167F(75C) conductorsRC
Input Power
Stage
2
Stage1
Boil System Pump
Mix System Pump
DHW Pump
VariableSpeed Pump
Pump Power L
402070
313
Single Boiler, 2 Boiler Zones, DHW, 3 Way Mix, 4 Mix Zones A402-2
S3
S1 S2
S4
24 V (ac)Transformer 009
Zone Valves (Z1 to Z4)
DHW Sensor (S4)
Boiler Sensor (S1)
Mix Sensor (S2)
tekmarNet2 Thermostats
OutdoorSensor
(S3)
tekmarNet4Expansion to
Wiring Centers,Timers, or
User Switch
tekmarNet2 ThermostatstekmarNet2 Thermostats
P1
P2
P3
Z1 Z2 Z3 Z4
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CallsCALLS
Displays any call for heat the control isreceiving.
PumpsPUMPS
Displays any pump currently operating.
Zones1 2 3 4
ZONES
Displays if an on-board zone is operating.
WARNING
Displays if an error exists on the system.
SavingENERGY SAVING INDICATOR
Displays when the system is saving energy.
See the Energy Saving Features section.
WWSDWWSD
Displays when the system is in WarmWeather Shut Down.
FC
minhr
sec%
F, C, %, HOURS, MINUTES, SECOND
Units of measurement for current number.
UNOCCUPIED
Indicates that a User Switch or Timer hasput the system into UnOccupied.
BOILER
Indicates that the boiler should beheating.
DEVICE OUTPUT SCALE
Displays output of the mixing valve orinjection pump.
ClsOpn
CLOSE / OPEN
Displays whether the mixing valve motor
is opening or closing.
MAXMINMIN / MAX
Displays when an operating temperaturereaches a minimum or maximum value.
Symbols
Display
MONITOR
VIEW
ADJUST
MAXMIN
Boil ExpMix Exp
DHW Setp
Boil SystemMix System Zones
ClsOpn
DHW Var 1 2 3 4 1 2 Mix
AM
minsec
hr
PMCalls Pumps WWSD Saving
Item Field
Displays the name
of the selected item
Number Field
Displays thecurrent value of
the selected item
Status Fields
Displays the currentstatus of the controls
inputs, outputs andoperation. Most symbols
in the status field areonly visible when the
VIEW Menu is selected
Menu Field
Displays thecurrent menu
User Interface
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Navigating The Display
Menu Button ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------The 402 uses a simple user interface to accomplish avariety of functions. The four buttons beneath the display
are used to change the menu, sort through Items, andadjust each setting as required.
The menus display in the Menu Field at the top left side ofthe LCD. Four menus are available: View, Adjust, Monitorand Toolbox (identified by the wrench symbol).
The View menu allows the user to view the currentstatus of various system parameters.
The Adjust menu allows the installer to adjust settings
to ensure control operation matches requirements ofthe mechanical system.
The Monitor menu keeps track of run times andother important data that is collected during systemoperation.
The Toolbox menu is a source of system informationand includes useful tools for commissioning and test-ing the system.
Item Button ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Each menu contains a list of Items that can be viewed and,in some cases, adjusted. Press the item button to scrollthrough the list in each Menu.
To view the next available item, press and release theItem button.
To view the previous item, hold down the Item button,and press and release the Up button.
Up and Down Buttons ----------------------------------------------------------------------------------------------------------------------------------------------------------------The Up and Down buttons are primarily used for adjustingsettings.
To adjust a setting:
Select the appropriate menu using the Menu button.
Select the item using the Item button.
Use the Up or Down button to make the adjustment.
Default Item ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------When navigating menus, the display reverts back to thedefault item (View Menu) after 60 seconds of buttoninactivity.
To set the default item in the View menu, display theitem for more than five seconds.
Access Levels and Thermostat Lock
The 402 is shipped pre-programmed with common settings.The 402 has an Installer access level that allows full accessto all settings and a User access level that restricts thenumber of settings to only the Warm Weather Shut Down
and the temperature units. The 402 defaults to the Useraccess level after 12 hours of operation.
All thermostats are locked while the 402 is in the Useraccess level. Certain settings on the thermostat will beunavailable while the thermostat is locked.
To change to the Installer access level and Unlock thethermostats:
In the Toolbox menu, locate Access
Adjust the access level to Installer by pressing theup or down button. This prevents unwanted setting
changes to the control.
Programming and Settings
The 402 settings can be found in the Adjust menu. Whenchanging the items value, the setting is saved to the controlsmemory once the Item button is pressed to advance to thenext item, or after 60 seconds, the control times out andreverts back to the View menu.
All settings are stored in permanent memory and will bekept correctly during any loss of power.
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Item Field Range Description
VIEW
Zones
Calls Pumps-76 to 149F(-60.0 to 65.0C)
OUTDOOR SECTION B, C
Current outdoor air temperature as measured by the outdoor sensor. Theoutdoor air temperature is shared to all thermostats in the tekmarNetsystem.
VIEW
Zones
Calls Pumps
-22 to 266F
(-30.0 to 130.0C)
MIX SUPPLY SECTION BCurrent mix supply water temperature as measured by the mix supplysensor. The control operates the mixing device so that the mix supplyis equal to the mix target temperature.
VIEW
Zones
Calls Pumps
, 35 to 180F
(1.5 to 82.0C)
MIX TARGET SECTION BThe temperature the control is currently trying to maintain at the mixsupply sensor. The mix target is calculated based on the outdoor
design and mix design settings. is displayed when no heat isrequired for mix zones.
VIEW
Zones
Calls Pumps
-22 to 266F(-30.0 to 130.0C)
BOILER SUPPLY SECTION CCurrent boiler supply water temperature as measured by the boilersensor. The control operates the boiler so that the boiler supply iswithin the boiler differential of the boiler target. MIN is shown whenthe control is providing boiler minimum protection to the boiler.
VIEW
Zones
Calls Pumps
, 35 to 200F(1.5 to 93.0C)
BOILER TARGET SECTION CThe boiler target is the temperature the control is currently trying tomaintain at the boiler supply sensor. The boiler target is calculated basedon the outdoor design, boiler design, and boiler minimum settings. is displayed when no heat is required for boiler zones. MIN is shown
when the control is providing boiler minimum protection to the boiler.VIEW
Zones
Calls Pumps 0-100%
BOILER MODULATION SECTION FCurrent percent modulation of the boilers burner. The boiler modulationincreases when the boiler supply is less than the boiler target. Theboiler modulation decreases when the boiler supply is greater than theboiler target.
Note:This item is only available when the Boil Type setting is set to0-10 or 4-20.
-22 to 266F(-30.0 to 130.0C)
DHW TANK SECTION DCurrent Domestic Hot Water tank temperature as measured by the optionalDHW sensor. If the DHW tank temperature falls 6F (3.0C) below theDHW Occ setting, a DHW call is created and the tank is heated.
Note: This item is only available when a DHW sensor is installed andDHW Mode is set to 1 to 4.
-22 to 266F(-30.0 to 130.0C)
DHW SUPPLY SECTION DCurrent supply water temperature to the indirect DHW tank heatexchanger as measured by the DHW sensor.Note: This item is only available when a DHW sensor is installed andDHW Mode is set to 5.
--
SYSTEM IN AWAY SECTION IThe heating system is in the Away scene. The DHW tank will not beheated. Setpoint calls are still responded to.Use the User Switch to change scene out of Away.
VIE
WMENU
View Menu (1 of 1)
The View menu items display the current operating temperatures and status information
of the system.
After the last item, the control returns to the first item in the menu.
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Item Field Range Access Description Set to
ADJUST -60 to 45F
(-51.0 to 7.0C)
Default = 10F
(-12.0C)
Installer
OUTDOOR DESIGN SECTION B, CTypically set to the temperature of the coldest dayof the year. The outdoor air temperature used in theboiler and mixing heating curves that determine theboiler target and the mix target temperatures.
ADJUST 70 to 180F
(21.0 to 82.0C)
Default = 120F
(49.0C)
Installer
MIX DESIGN SECTION B
The supply water temperature required for the mixzones to heat the building on the typical coldest dayof the year. Recommendations:High mass radiant floor = 120F (50C)
Low mass radiant floor = 140F (60C)
Fancoil or air handling unit = 190F (90C)Copper fin-tube convector = 180F (80C)
Radiators = 160F (70C)Low profile baseboard = 150F (65C)
ADJUST4-20 mA,
0-10 V (dc)
FLOT,
VAR
Default = VAR
Installer
MIX TYPE SECTION B
Select the type of mixing device.
VAR = Variable speed injection pumpFLOT = Floating action motor for mixing valves
0-10 = 0 -10 V (dc) analog signal for mixing valves4-20 = 4-20 mA analog signal for mixing valvesNote:0-10 and 4-20 are only available when BoilerType = 1 Stage or 2 Stage.
ADJUST
sec 30 to 230 seconds
Default = 105 secondsInstaller
MIX MOTOR SECTION B
The time that the mix actuating motor requires tooperate from fully closed to fully open.
tekmar actuating motors = 105 sec.Refer to actuating motor for correct setting.Note:This item is only available when the Mix Typeis set to FLOT (floating action motor), 0-10, or 4-20.
EMS2,
EMS1,4-20
0-10,
2STG,
1STG
Default = 1STG
Installer
BOILER TYPE SECTION F
The type of boiler connected to the control.1STG = single one-stage on-off boiler
2STG = single two-stage on-off boiler0-10 = 0-10 V (dc) modulating boiler
4-20 = 4-20 mA modulating boilerEMS1 = tekmar boiler staging controls
EMS2 = Viessmann modulating boilers withOpenThermNote:Only 1STG and 2STG are available when theMix Type is set to 0-10 V (dc) or 4-20 mA.
ADJ
USTMENU
Adjust Menu (1 of 3)
The Adjust menu items are the programmable settings used to operatethe mechanical equipment.
Continued on next page.
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Item Field Range Access Description Set to
VIEW
70 to 200F
(21.0 to 93.5C)
Default = 180F(82.0C)
Installer
BOILER DESIGN SECTION C
The supply water temperature required for the boilerzones to heat the building on the typical coldest dayof the year. Recommendations:High mass radiant floor = 120F (50C)
Low mass radiant floor = 140F (60C)Fancoil or air handling unit = 190F (90C)
Copper fin-tube convector = 180F (80C)Radiators = 160F (70C)
Low profile baseboard = 150F (65C)
OFF, 80 to 180F
(26.5 to 82.0C)
Default = 140F(60.0C)
Installer
BOILER MINIMUM SECTION B, C
The minimum allowed boiler target temperature andtemperature at which the mixing device begins toprovide boiler protection against cold return watertemperatures. The mixing valve or variable speedinjection pump operate at low percent output whenthe boiler supply temperature drops below thissetting.
Recommendations:Condensing gas or electric boiler = OFF
Non-condensing gas and oil boilers = 140F (60C)Note:If Boiler Type is 0-10 V (dc), 4-20 mA, EMS1or EMS2, this setting is defaulted to Off. The mixingdevice does not provide boiler protection when BoilerType is set to EMS1 or EMS2.
ADJUST
sec
10 to 230 seconds
Default = 30
secondsInstaller
BOILER MOTOR SECTION F
The time required for the modulating actuating motorto fully open the gas valve or ramp the burner fanfrom off to full speed on a modulating boiler. Set to30 seconds unless otherwise recommended by the
boiler manufacturer.Note:This item is only available when the BoilerType is 0-10 V (dc) or 4-20 mA.
ADJUST
0 to 50%
Default = 0%Installer
MINIMUM MODULATION SECTION F
The minimum percent modulation of the boilerburner.
Note:This item is only available when the BoilerType is 0-10 V (dc) or 4-20 mA.
ADJUST
sec
0 to 3:00 minutes
Default = 10seconds
Installer
MODULATION DELAY SECTION F
Delay time between the burner firing and the boiler
releasing to modulation.Note:This item is only available when the BoilerType is 0-10 V (dc) or 4-20 mA.
ADJUST
Off or On
Default = OffInstaller
FLUSHING SECTION G
Set to On when a domestic hot water tank is usedto heat the building. When On, the control ensuresthat each zone is operated at least once daily toprevent stagnation.
Adjust Menu (2 of 3)
A
DJUSTMENU
Continued on next page.
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Item Field Range Access Description Set to
ADJUST 40 to 100F
(4.5 to 38.0C)
Default = 70F
(21.0C)
Installer
User
WWSD OCCUPIED SECTION I
The systems Warm Weather Shut Down temperatureduring Occupied periods or when a schedule is notused.
ADJUST 40 to 100F
(4.5 to 38.0C)
Default = 60F
(15.5C)
Installer
WWSD UNOCCUPIED SECTION I
The systems Warm Weather Shut Down temperatureduring Unoccupied periods.Note:Item is only available when a schedule or UserSwitch is present on the system.
Off, 1, 2, 3, 4, 5
Default = 2Installer
DHW MODE SECTION D
Selects the DHW mode of operation. Themode determines the zone and boiler systempumps operation whenever the DHW pump is inoperation.
100 to 200F
(38.0 to 93.5C)
Default = 180F(82C)
Installer
DHW EXCHANGE SECTION D
Selects the minimum boiler target to the DHW heatexchanger.Note:Item is only available in DHW Modes 1 through 4when a DHW sensor is not connected. It is available inDHW Mode 5 when a DHW sensor is connected.
70 to 180F
(21.0 to 82.0C)
Default = 125F
(51.5C)
Installer
DHW OCCUPIED SECTION D
Selects the temperature of the indirect DHW tank.
Note:Item is only available when an optional DHWsensor is installed except in DHW Mode 5.
ADJUST
Off or On
Default = OnInstaller
DHW UNOCCUPIED SECTION I
Selects whether or not the indirect DHW tank shouldbe heated to during Unoccupied time periods.Note: Item is only available when Schedule #1is available or a User Switch is present on thesystem.
ADJUST 60 to 200F
(15.5 to 93.5C)
Default = 180F
(82.0C)
InstallerSETPOINT SECTION E
The minimum boiler target temperature when aSetpoint Call is present.
ADJUST
F or C
Default = F
Installer
User
UNITS
Selects units for temperature display.
Adjust Menu (3 of 3)
ADJUSTMENU
After the last item, the control returns to the first item in the menu.
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Item Field Range Description
On or Off
Default = Off
USER TEST TESTING
Begins the test routine which tests the main controls functions.See the Testing the Control section for more details. Use theup button to turn the User Test On.
On or Off
Default = Off
MAX HEAT TESTING
When selected, control operates the system up to maximum settemperatures. Will operate up to 24 hours, or can be manuallyturned Off. See Max Heat in the Testing the Control sectionfor more details.
402
J12 06B
TYPE AND SOFTWARE VERSION
Displays the type number of the product, followed by the currentsoftware version beneath.
INST (Installer)
or USER
Default = INST
ACCESS LEVEL
Selects the Access Level of the control, which determines theMenu items available. USER provides the most limited level ofaccess and shows the fewest possible items.
When set to USER, all thermostats are locked and the numberof thermostat settings available are reduced.
OFF, SEL
Default = Off
FACTORY DEFAULTS
Loads the factory default settings. Hold the Up and Downbuttons for 1 second until SEL is shown.
0 to 24 devices
MIX DEVICES
Displays the number of devices on the Mix bus (WaterTemperature). This is made up of thermostats connected tothe House Control, and to the Mix Expansion terminals.
0 to 24 devices
BOIL DEVICESDisplays the number of devices on the Boil Expansion bus(Water Temperature). This is made up of thermostats connectedto the Boil Expansion terminals on the House Control.
See Troubleshooting
Guide
HISTORY - 1 THROUGH 5
Displays a history of any past errors that have occurred on thesystem. Will clear after 30 days, or press Up and Down buttonsfor 1 second to manually clear. The last 5 history items willdisplay if present.
TOOLB
OXMENU
After the last item, the control returns to the first item in the menu.
The Toolbox Menu is a location for system information andTest functions. If any errors are present on the system, theywill be located at the beginning of this menu.
Toolbox Menu (1 of 1)
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Sequence of Operation
tekmarNetSystem Section A
tekmarNet is a family of products that use communicationto operate the HVAC system in a comfortable and efficientmanner. The House Control is the central component ina tekmarNet system and requires tekmarNet2 (tN2)Thermostats to be directly connected to the control.
The tekmarNet4 (tN4) Expansion terminals can link theHouse Control with other tekmarNetcomponents:
Wiring Centers 313, 314, 315, 316 - Add additional zones
tN2 and tN4 Thermostats - Add thermostats
tN4 Timer 033 - Adds 4 programmable schedules
tN4 User Switch 479 - Provides a system override forvacations and holidays
tN4 Setpoint Control 161 - Control hot tubs, pools andmore
Mix Temperature Reset Operation Section B
When an onboard tN2 Thermostat calls for heat, the HouseControl registers a Mix call for hydronic heating.
When a device connected to the tN4 Mix Expansionterminals calls for heat, the House Control registers a MixExpansion Call for hydronic heating on the mix loop.
Mix
Calls
Mix Exp
Calls
Mix Call or Mix Expansion Call ----------------------------------------------------------------------------------------------------------------------------------------------
Mix Target----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------When there are no Mix or Mix Expansion calls, the mixtarget in the View menu on the display will show toindicate there is no requirement for mixing operation.
Once a Mix Call or Mix Expansion Call is present, a mixtarget is determined by the control using the mixing heatingcurve (mix design and outdoor design settings) togetherwith indoor temperature feedback from the thermostats.The heating curve operates based on the principle thata buildings heat loss increases with colder outdoor
temperatures. The calculated Mix Target will be shown inthe View menu on the display.
Mix Maximum
The control has a fixed mix maximum temperature of +10F(+5.5C) higher than the Mix Design set ting. When thisoccurs, the MAX segment will display when viewing the
mix target or mix supply temperature in the view menu.
Mix Heating Curve
(70F Outdoor,
70F Mix Supply)
Decreasing Outdoor TemperaturesIncreasingWaterTemperatures
(Outdoor Design,Mix Design)
Mix Supply --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Once a Mix Target water temperature has been calculated,the House Control measures the temperature at the mix
supply sensor location and then operates the mixing deviceto maintain the mix supply temperature. The heat source willalso be turned on and operated so that the mixing deviceis able to maintain the mix target temperature.
Boiler Minimum ProtectionIf the boiler supply water temperature is cooler than the
boiler minimum setting, the control reduces the output of themixing device. This limits the amount of cool return wate
to the boiler and allows the boiler return water temperatureto recover. Once the boiler supply temperature exceedsthe boiler minimum setting, the mixing device will returnto normal operation.
Note: The mixing device does not provide boiler minimumprotections when the Boiler Type setting is EMS1 or EMS2
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Mixing Device Type----------------------------------------------------------------------------------------------------------------------------------------------------------------------The House Control can operate a mixing device such asa mixing valve or variable speed injection pump basedupon one of four output signals. The device output bargraph on the display indicates the approximate positionof the mixing device.
Variable Speed Injection PumpA standard wet rotor circulator can be connected to theVariable Speed Pump output on the back of the control.The control varies the circulator speed to maintain thecorrect mixed supply water temperature at the mix supplysensor. For correct sizing and piping of the variable speedinjection circulator, refer to essay E 021. Note: Pumpsmanufactured with an internal variable speed controllerare not compatible with the House Control.
Floating Action 24 V (ac)
A 24 V (ac) floating action actuator motor and mixing valvecan be connected to the Floating Action outputs on thefront of the House Control. The control pulses the actuatormotor open or closed to maintain the correct supply watertemperature at the mix supply sensor when there is a
requirement for mixing.
Modulating 0-10 V (dc)
*Only available if a one or two stage on-off boiler isused.
A modulating 0-10 V (dc) actuating motor can be used to
operate the mixing valve. The control uses the Mod dc/mAoutput to provide an analog 0-10 V (dc) signal to the actuatorin order to maintain the correct mix supply temperature.
Modulating 4-20 mA*Only available if a one or two stage on-off boiler isused.
A modulating 4-20 mA actuating motor can be used tooperate the mixing valve. The control uses the Mod dc/mAoutput to provide an analog 4-20 mA signal to the actuatorin order to maintain the correct mix supply temperature.
Mixing Device ExercisingThe control operates the mixing device from 0 to 100% outputevery 3 days to help prevent corrosion and / or precipitatebuild up on the mixing valve or pump that could lead toseizure of the mixing device. The control ensures that no
heat is supplied to the zones during exercising.
Boiler Temperature Reset Operation Section C
Boiler Expansion Call ----------------------------------------------------------------------------------------------------------------------------------------------------------------Boil Exp
CallsWhen a device connected to the tN4 Boil Expansionterminals calls for heat, the House Control registers a BoilExpansion call for hydronic heating on the boiler loop.
Boiler Target ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------When there are no Boiler Expansion or Mix calls, the boilertarget in the View menu on the display will show to
indicate there is no requirement for boiler operation.
Once a Boiler Expansion Call is present, a boiler targetis determined by the control using the boiler heatingcurve (boiler minimum, boiler design and outdoor designsettings) together with indoor temperature feedback from
the thermostats. The heating curve operates based on theprinciple that a buildings heat loss increases with colderoutdoor temperatures. The calculated Boiler Target will beshown in the View menu on the display.
When a Mix or Mix Expansion Call is present, the control
calculates a boiler target that is higher than the mix targetusing Boiler Load Reset.
Boiler Minimum
The House Control protects non-condensing boilers fromsustained flue gas condensation and thermal shock throughthe Boiler Minimum setting. The boiler minimum is thelowest temperature that the control is allowed to use as a
boiler target temperature. If the boiler is operating at theboiler minimum temperature, the MIN segment is turnedon in the display when viewing either the boiler supplytemperature or the boiler target temperature.
Boiler Heating Curve
(70F Outdoor,
Boiler Minimum)
Decreasing Outdoor TemperaturesIn
creasingWaterTemperatures
(Outdoor Design,Boiler Design)
Boiler Maximum
The control has a fixed boiler maximum temperature of +
10F (+5.5C) higher than the Boiler Design setting for theBoiler Heating Curve. When this occurs, the MAX segmentwill display when viewing the boiler target or boiler supplytemperature in the view menu. The control will operatethe boiler so that the boiler supply temperature will never
exceed 210F (99.0C).
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Domestic Hot Water Tank Operation Section D
A DHW Call is required in order for the control to provide
heat to a DHW tank. Once the control registers a DHW Call,it will display the DHW icon under Calls in the display.This can be done in three ways:
DHW Tank Aquastat
If a DHW aquastat (mechanical switch) is used toapply a DHW Call, the tank is heated to the aqua-stat temperature setting. A dry contact or 24 V (ac)
signal is applied across the DHW Call terminals on theHouse Control.
DHW Tank Sensor
A DHW tank sensor provides superior temperature
control of the tank compared to an aquastat. TheHouse Control automatically detects whether a DHW
sensor is installed. The upper limit of the DHW tem-perature is set by the DHW setting. The DHW tank dif-
ferential is fixed to 6F (3C).
DHW
Calls
DHW Call------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
DHW Mode --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------The control has five different settings available for DHWMode that affect pump operation. The required DHW
Mode setting will depend on the piping arrangement of theDHW tank and whether or not priority for the DHW tankis necessary. DHW Priority stops or limits the delivery of
heat to the building heating system while the DHW tankcalls for heat. This allows for quick DHW tank temperaturerecovery.
DHW MODE 1 - DHW in Parallel no Priority
When a DHW Call is present, the DHW pump is activated.The boiler system pump does not turn on, but may operatebased on either a Boiler, Mixing, or Setpoint Call.
It is assumed that the DHW pump will provide adequateflow through the heat exchanger and the boiler.
DHW MODE 2 - DHW in Parallel with Priority
When a DHW Call is present, the DHW pump is activated.The boiler system pump and all boiler temperature zones
are shut off through tekmarNetcommunication to achieveDHW priority.
It is assumed that the DHW pump will provide adequateflow through the heat exchanger and the boiler.
DHW - Boiler Target --------------------------------------------------------------------------------------------------------------------------------------------------------------------When a DHW Call is present, a boiler target isdetermined.
When using a DHW Tank Aquastat, the boiler target isset to the DHW Exchange setting.
When using a DHW Tank Sensor, the boiler target is
set to the DHW Occupied setting plus 40F (22C).
ON Or OFF
ON
DHWPump
ON OrOFF
ZoneValve
Boiler SystemPump
DHW Mode = 1
OFF
ON
DHWPump
OFF
ZoneValve
Boiler SystemPump
DHW Mode = 2
When using a tekmarNetSetpoint Control, the boilertarget is set to the devices Exchange Supply setting.
If there are multiple devices calling for heat, the boiler targeis set to the highest temperature requirement.
tekmarNetSetpoint Control with Sensor
A DHW Call is provided through the tekmarNetsystem. This can be done through the Boil Expansion
tN4 terminals with a tekmarNetsetpoint device suchas a Setpoint Control 161.
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DHW MODE 3 - DHW in Primary / Secondary noPriority
When a DHW Call is present, the DHW pump and the boilersystem pump is operated. Boiler temperature zones canturn on if required.
DHW MODE 4 - DHW in Primary / Secondary withPriority
When a DHW Call is present, the DHW pump and theboiler system pump is operated. All boiler temperaturezones are shut off through tekmarNetcommunication toachieve DHW priority.
DHW Mode 5 - DHW in Near Boiler Piping withPriority
DHW Mode 5 requires that a DHW sensor be located onthe boiler outlet pipe and a DHW call from an aquastatinside the DHW tank. The aquastat operates the DHWtank temperature while the DHW sensor is used to controlthe boiler temperature delivered to the DHW indirect heatexchanger.
When a DHW Call is present, the DHW pump is activated.The boiler system pump and all boiler temperature zones
are shut off through tekmarNetcommunication to achieveDHW priority.
It is assumed that the DHW pump will provide adequateflow through the heat exchanger and the boiler.
DHW Priority Override----------------------------------------------------To prevent the building from cooling off too much or thepossibility of a potential freeze up during DHW priority,
the control limits the amount of time for DHW priorityduring cold weather. During warm weather the DHW
priority is 120 minutes. During cold weather the DHW
priority is 15 minutes. Once the allowed time for priorityhas elapsed, the control overrides the DHW priority andresumes space heating for 15 minutes. It will then revertback to DHW Priority and repeat.
DHW Post Purge ------------------------------------------------------------After the DHW Call is removed, the control performs a purgeon the boiler. The control shuts off the boiler and continuesto operate the DHW pump and the Boiler System pump ifapplicable. This purges the residual heat from the boilerinto the DHW tank. The control continues this purge for a
maximum of two minutes. The control also stops the purge
if the boiler supply temperature drops below the currentboiler target temperature.
Boiler SystemPump
DHWPump
ZoneValve
ON
ONON OrOFF
DHW Mode = 3
Boiler SystemPump
DHWPump
ZoneValve
ON
ONOFF
DHW Mode = 4
OFF OFF
DHWSensor
ON
DHWPump OFF
ZoneValve
Boiler SystemPump
BoilerPump
BoilerSensor
DHW Mode = 5
DHW Priority Override Time
IncreasingTime
Decreasing Outdoor Air Temperature
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Setpoint Operation Section E
A Setpoint Call is required in order for the control to provideheat to a setpoint load, such as a spa, pool, or snowmeltload. This can be done in two ways:
Contact Closure----------------------------------------------------------------A dry contact or 24 V (ac) signal is applied across theSetpoint Call terminals on the 402.
tekmarNet
Setpoint Control with Sensor--------------A Setpoint Call is provided through the tekmarNetsystem. This can be done through the tN4 Expansion
terminals with a setpoint device such as a SetpointControl 161.
Once the control registers a Setpoint Call, it will displaythe Setp icon under Calls in the display.
Note: Setpoint operation has a fixed priority of on.
Setpoint Operation ----------------------------------------------------------The control can operate to satisfy the requirements of asetpoint load in addition to a space heating load and a
DHW load. A setpoint load overrides the current outdoor
reset temperature and WWSD setting in order to provideheat to the setpoint load.
Setpoint Priority
Boiler System PumpIf Mix demand = OnOtherwise = Off
SetpointPump
Setpoint
ON
ZoneValveOFF
When the control receives a Setpoint Call:
All Boil zones are turned off.
The Mix device is ramped down to a minimum level.
The boiler will operate to maintain the Setpoint tem-
perature as set in the Adjust menu, or as set on thetekmarNet Setpoint control if one is being used.
Setp
Calls
It is assumed that the Setpoint pump will provide adequateflow through the heat exchanger and the boiler.
Setpoint calls will also be responded to when the system
is in Away, which can be set using a 479 User Switch.
Setpoint Priority Override --------------------------------------------To prevent the building from cooling off too much orthe possibility of a potential freeze up during setpoint
priority, the control attempts to limit the amount of timefor setpoint priority.
As the outdoor air temperature becomes colder, the lengthof time the control provides setpoint priority is reducedOnce the allowed time for priority has elapsed, the controwill check the space heating target.
If there is a space heating target, the boiler operates athat target for 15 minutes.
If after 15 minutes there is still a Setpoint Call, the con-trol will reduce mixing outputs, shut off all boiler heat-
ing zones and target the Setpoint temperature.
Note: It is possible to disable Setpoint Priority by using
a tekmarNetSetpoint control and turning the priorityto Off in the Setpoint control.
Boiler Operation Section F
The 402 is able to operate a single 1-stage or 2-stage on-off boiler or a single modulating boiler as a heat source.For proper operation of the boiler, the 402 must be the onlycontrol that determines when the boiler is to fire.
*Important note:The operating control in the boiler, also
known as an aquastat, remains in the burner circuit and actsas a secondary upper limit on the boiler temperature. Theboiler operator temperature setting can be adjusted above
210F, which is the fixed Boiler Maximum on the 402.Boiler Target Temperature--------------------------------------------The boiler target temperature is the temperature which
the control is trying to operate the boiler at. There arefour items that determine the boiler target temperature:
Mix Call
Boil Exp Call
DHW Call
Setpoint Call
If the control receives more than one call for heat at thesame time, it will operate the boiler at the highest of thefour calls.
The control displays the temperature that it is currentlytrying to maintain as the boiler supply temperature in the
View menu. If the control does not presently have a call foheat, it does not show a boiler target temperature. Instead is displayed on the LCD.
Boiler Minimum ----------------------------------------------------------------When operating non-condensing boilers, it is importantto prevent cool water from returning to the boiler. Cold
return temperatures create flue gas condensation, whichif left too long, can severely damage the boiler.
The 402 protects the boiler through the Boiler Minimumsetting. The boiler minimum is the lowest temperature thathe control is allowed to use as a boiler target temperatureIf the boiler is operating at the boiler minimum temperaturethe MIN segment is turned on in the display when viewingeither the boiler supply temperature or the boiler targetemperature.
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Boiler Maximum----------------------------------------------------------------The 402 will operate the boiler so that the boiler
supply temperature will never exceed 210F (99.0C).The highest allowed boiler target is the boiler designtemperature + 10F (5.5C).
Boiler Type--------------------------------------------------------------------------The 402 can operate either of the following types ofboilers:
One single-stage on-off boiler
One two-stage on-off boiler
Modulating boiler using a 0-10 V (dc) signal
Modulating boiler using a 4-20 mA signal
tekmar EMS signal (for use with multiple boiler
stagers)
EMS signal for Viessmann modulating boilers
On-Off Operation--------------------------------------------------------------The 402 operates a single hot-water on-off boiler tomaintain the boiler target within a differential. The boilertarget is the average temperature and the boiler supply
temperature can fluctuate by 1/2 of the differential aboveand below of the boiler target.
Modulation Boiler Operation --------------------------------------The 402 can operate a single hot-water modulating
boiler using the Mod dc/mA output and the Boiler Stagecontact. Not all boilers require the use of the Boiler
Stage contact.
The control operates the boiler by first switching the boilerstage contact to allow the modulating boiler to go throughthe ignition sequence (the boiler stage contact may notbe required on all modulating boilers). A 0-10 V (dc) or 4-20 mA analog signal is then used to modulate the boilerfiring rate star ting from 50% (5 V (dc) or 12 mA signal) for30 seconds.
After the 30 second delay has elapsed, the control willthen allow the boiler to modulate down to the minimummodulation setting and hold it there for the Modulation Delaytime setting. The Modulation Delay setting is determinedby the boiler manufacturer. It is the amount of time thatthe burner must operate before the internal boiler controlallows an external signal to operate the burner.
After the Modulation Delay has elapsed, the control usesPID logic to change the boiler firing rate signal in orderto satisfy the boiler target temperature. When the firingrate signal is reduced down to the Minimum Modulatingsetting and the boiler supply temperature exceeds the
boiler target by 1/2 of the differential, the control will shutoff the burner.
Minimum Modulation
The Minimum Modulation is the lowest signal the controlcan send to modulate the boiler. This operates the boiler
at low fire.
Refer to the boiler manufacturers literature to deter-mine the minimum output voltage V (dc) or current
(mA) that the boiler will successfully operate at.
For 0-10 V (dc):
Minimum Modulation =Boilers Minimum Input Signal x 100%
10 V (dc)
For 4-20 mA:
Minimum Modulation =
Boilers Minimum Input Signal - 4mA x 100%
16 mA
Example:
A boiler requires a 1.8 V (dc) signal to fire the boiler atlow fire. The boiler can be modulated to 10 V (dc) whereit reaches high fire.
Minimum Modulation = 1.8 V x 100% = 18%10 V
1.8 V (dc)
10 V (dc)
Control
Range
Boiler
Range
0 Vdc
18%
tekmar EMS Signal Operation
The 402 can provide a 0-10 V (dc) signal proportional tothe boiler target which is compatible with tekmar BoilerStaging controls that accept an EMS input.
To use the tekmar EMS signal operation, the Boil Type
setting in the Adjust menu must be set to EMS1.
Viessmann EMS Signal
The 402 has a special 0-10 V (dc) signal proportional tothe boiler target that is designed to be compatible withViessmann Open Therm 0-10 V (dc) inputs.
To use the Viessmann EMS signal operation, the Boil
Type setting in the Adjust menu must be set to EMS2.The signal is 0 V (dc) when the boiler is off. The voltageis 2.2 V (dc) to provide a boiler target of 81F (27C),up to maximum of 10 V (dc) to provide a boiler target of176F (80C).
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Auto Differential----------------------------------------------------------------Both on-off and modulating boilers are operated witha differential. In some cases, a modulating boiler mustbe operated with a differential while operating at low
fire because this indicates the load is smaller thanthe minimum modulation of the boiler. For modulating
boilers, the differential no longer applies once operatingthe boiler above low fire.
The differential operates by closing the boiler contact
when the boiler supply water temperature is 1/2 of thedifferential below the boiler target temperature. As thesupply temperature reaches 1/2 of the differential abovethe boiler target temperature, the boiler is shut off.
+1/2 Differential
- 1/2 Differential
Boiler Target
Boiler On
Boiler Off
In order to decrease temperature swings and increase boileefficiency, the Auto Differential feature automatically adjuststhe operating differential of the boiler based on the heatingload. As the load increases, the differential will decrease
to minimize temperature swings. As the load decreasesthe differential will increase to prevent short cycling. This
can significantly improve operating efficiency and prevenequipment failures through excessive cycling.
Off
Differential
Time
Heating
Load
On
Domestic Hot Water Heat Source Section G
The 402 can use a high-efficiency water heater as a sourceof heat for space heating zones in addition to providingdomestic hot water. This is an open-loop system in whichpotable water is circulated through the zones. When theflushing feature is set to on, the mixing valve is moved to thefully open position, all four zone valves are opened, and themix system pump is turned on for 5 minutes each day. Thisprevents stagnation of the water in the heating system.
402070
Pump Operation Section H
Mix System Pump ------------------------------------------------------------The mix system pump operates whenever all thefollowing conditions are met:
A Mix Call is present.
The thermostat calling for heat has the Heat 1 pumpsetting set to On.
The heating system is not in Warm Weather Shut Down.
Boiler System Pump--------------------------------------------------------The boiler system pump operates whenever all the
following conditions are met:A Mix or a Boiler Call is present.
The thermostat calling for heat has the Heat 1 pump
setting set to On.
There is no DHW priority.
The heating system is not in Warm Weather Shut Down.
DHW Pump--------------------------------------------------------------------------The DHW pump operates whenever all the following
conditions are met:
A DHW Call is present.
The heating system is not in DHW priority override.
DHW post purge.
Variable Speed Injection Pump ----------------------------------The variable speed pump operates whenever thefollowing conditions are met:
A Mix Call is present.
The heating system is not in Warm Weather ShutDown.
Note: The variable speed pump operates at minimumspeed whenever the boiler supply temperature falls belowthe boiler minimum setting and whenever there is a DHWCall and DHW priority has been selected.
Pump Exercising ------------------------------------------------------------The control operates each pump every three days for 10seconds to help prevent corrosion and / or precipitate buildup on the pump components that can lead to pump seizureThe control ensures that no heat is supplied to the zonesduring exercising.
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