refrigerant r-410a & r-22 this is your program/time: ask questions, use your time...

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Refrigerant R-410A & R-

22

This is your program/time: ask questions, use your time wisely…it’s not the cost of the program (money

wise), but your time spent here that is important…dollar wise, this is cheap,

however you /me only have 24 hours/day in that respect we are all equal…but it’s how you spend that

time that is important….

Questions?/Comments!

Feel free at any time to ask questions, or to make a comment. There are NO dumb questions….only the answers!!!And the instructors are responsible for those.This is your meeting, enjoy and participate……..

Service Advisors

Gustave A. Larson Company

Plymouth Office: 800-827-9508

763-546-9508

Gale Patterson ext. 343

Steve LeMay ext. 346

Pewaukee Office: 800-829-9609

Steve Bukosky ext. 247

Larry Lemens ext. 285

Thermodynamics

Saturation Temperature Density of Refrigerant Vapor Enthalpy Superheated Vapor Subcooled Liquid

Heat Transfer

Hot Object Cold Object

HEAT

Latent and Sensible Heat

212

0

32

One pound of water being heated at one BTU per hour.

Temperature of thewater.

1310 total BTU’s used.

16 144 180 966158 340 1306

Con

den

ser

Evaporator

Compressor

Thermostatic Expansion Valve

Basic Refrigeration

Dis

ch

arg

e L

ine

Condenser

Compressor

Suction Line

Evaporator

Thermostatic Expansion Valve

Liquid Line

Refrigerant Piping

¡(High Side)

¡(Low Side)

What does Saturation Temperature Mean?

1. Saturation Temperature is the actual temperature of the evaporator and condenser coils.

2. In saturation conditions vapor & liquid are present.

Saturation Temperature

How Do You Find Saturation Temperature?

Refrigeration Gauges>The Only Purpose of Owning a Set of Refrigeration Gauges Is to Find the RefrigerantSaturation Temperature.

Saturated Refrigeration

Example: Conditions, R-22 - 287 PSIG

128°F Temperature

P-T Chart at 287 PSIG R-22 = 128°F

Line Temperature = 128°F

Refrigerant is Saturated

Liquid and Vapor in Contact with Each Other in Equilibrium

Pressure and Temperature Tied Together

P/T Chart is Applicable

Saturated Refrigerant

Pressure/Temperature Chart

Liquid Line

Thermostatic

Expansion Valve

Suction Line

EvaporatorCondenserD

isch

arg

e L

ine

Compressor

Saturated Refrigerant

Sensible And Latent Heat TransferIn the Evaporator Coil

1. Latent Heat Transfer: -Greatest ability to absorb heat -Causes change of state -Refrigerant remains saturated2. Compressors cannot pump liquid3. Sensible Heat Transfer: -Heat added to refrigerant/no change in state - Superheated condition

Latent and Sensible Heat Transfer in

the Evaporator Coil

A B C D E

Thermodynamics/Evaporator

#1-Saturation Temperature:1. If any heat is added or removed to the temperature, at a given pressure a change ofstate occurs.2. At saturation temperature, both liquidand vapor are present.3. The saturation temperature is the temperature of the evaporator coil.

Thermodynamics/Evaporator (con’t)

#2-Suction Vapor Density:1. This is the weight of the refrigerant vapor,in Pounds per Cubic Foot Of Vapor.2. Suction Vapor Density causes the compressor to vary in amperage draw.3. Suction Vapor Density causes the system’spressures to rise and fall.

Thermodynamics And TheEvaporator Cycle (Summary)

The refrigerant in low pressure side of refrigeration cycle goes through three (3) changes:1. Saturation Temperature2. Suction Vapor Density3. Superheating of Suction Vapor

Thermodynamics/Evaporator

-Superheating Of Suction Vapor:

1. Superheat is the temperature of the vaporabove its saturation temperature.2. Superheat is done by the load.3. Superheating is a Sensible Heat Transferproviding very little cooling effect.

Heat Added to Refrigerant Vapor that Causes its Temperature to Rise Above its Saturation Temperatures

P/T Charts Do Not Apply - Temperature Rises Without a Rise in Pressure

Superheated Refrigerant

Example: Conditions, R-22 - 75.0 PSIG

Suction Line - 54°F

Line Temperature = 54°F

P-T Chart at 75.0 PSIG = 44°F

10°F Coil Operating at 10°F

Superheat

Superheating

212

0

32

One pound of water being heated at one BTU per hour.

Temperature of thewater.

1310 total BTU’s used.

16 144 180 966158 340 1306

Condenser

Compressor

Suction Line

Evaporator

Liquid Line

Thermostatic

Expansion Valve

Dis

ch

arg

e L

ine

Superheated Refrigerant

Sub-CoolingExample: Conditions, R-22 - 280

PSIG

120°F Line Temperature

P-T Chart at 280 PSIG = 125°F

Line Temperature = 120°F

5°F

Refrigerant Sub-cooled at 5°F

Heat Removed from the Liquid Refrigerant that Causes its Temperature to Drop Below its Saturation Temperature

P/T Charts do not Apply- Temperature Drops without a Drop in Pressure

Sub-Cooling

Thermodynamics/Condenser Coil

-Purpose of condenser coil is to reject the heat load absorbed by evaporator coil, and to cool the refrigerant to a level that is below the saturation temperature.-This is accomplished through (1) Latent Heat Transfer, and (2) Sensible Ht. Transfer.-Proper sub-cooling prevents saturated refrigerant from leaving the condenser, thus optimizing metering device performance.

Sub-Cooled Liquid-Typical subcooling levels - 5 to 20 degrees-Not enough subcooling, or large pressure losses in the liquid line create the formation of flash gas will affect the operation of the metering device.-10 degrees overcomes 35PSIG of liquid line pressure drop in R-22 systems.-10 degrees overcomes 50PSIG of liquid line pressure drop in R-410A systems.

Condenser

Liquid Line

Thermostatic

Expansion Valve

Evaporator

Compressor

Suction Line

Dis

ch

arg

e L

ine

Sub-Cooled Liquid

Liquid Line

Thermostatic

Expansion Valve

Condenser

Compressor

Suction Line

Dis

ch

arg

e L

ine

Evaporator

Three Conditions of the Refrigerants

Another New Refrigerant

In 1987 the world approved the Montreal Protocol and the United States wrote it in to law.

The law states that refrigerant R-22 can not be used in the manufacturing of new equipment after 2010.

In the mid 80s Trane began testing alternate refrigerants.

A New Refrigerant(con’t)The Trane Company found R-

410A to be one of the best alternate refrigerants available.

When it became apparent that R-410A would be the next main stream refrigerant, Trane began national field testing (prior to 96, field testing had only been done on a limited basis).

HCFC Cap and Future Production - The Cost of Future Service

0

5

10

15

20

25

30

1996 2000 2003 2004 2008 2009 2012 2014 2015 2016 2020

U.S

. P

ro

d. (M

. to

ns

) .

Projected U.S. Refrigerant Demand

HCFC (R-22) Phaseout in U.S.

Usage-Forecast and Montreal Protocol Cap

0

2

4

6

8

10

12

14

16

18

1985 1990 1995 2000 2004 2009 2013 2017 2021 2026

Years

CF

C E

qu

ival

ent

- M

Kg

Usage

Protocol

What about R-22?

¿ R-22 can be produced until 2020 for the service of installed systems.

¿ Reclaimed R-22 may be available forever!

¿ R-22 is not expected to see the drastic price increases as R-12 did, most the result of taxes.

What is R-410A?

R-410A is a blend of two refrigerants, near Azeotropic mixture of 50% HFC-32 and 50% HFC-125.

Many of us have been using refrigerant blends for awhile, R-502.

The Temp. Glide is negligible (< 0.3°F). There is no significant change in

composition due to system leaks.

What is R-410A?

The Ozone depletion potential(ODP) for R-410A is 0.00 Vs 0.05 for R-22 (1.0 is R-12 which is the baseline established by EPA).

The ASHRAE safety classification is A1/A1, the same as R-22.

Boiling point is -62.9°F Vs -41.4°F for R-22.

WHAT IS A1/A1

• A rating is an indication of no toxicity at concentrations of less than 400 ppm.

• 1 is a flammability classification that indicates no flame propagation.

• There are two ratings because R410A is a blend of different two refrigerants.

WHAT IS R-410A?

Thermal stability is similar to R-22.

Handling cautions are the same as R-22.

Remember 50 to 70% higher pressures require the proper tools for servicing.

R-410A … POE Oil

• Oil is different than R-22– polyolester rather than mineral oil.. POE

• POE is hygroscopic. It absorbs moisture rapidly. – Liquid line driers must be changed when

the system has been open. A good vacuum will not get all the water out.

POE Oils

Non-contaminated POE oils will not harm skin.

Non-contaminated POE oil has a light sweet odor.

POE’s are classified as non-hazardous.

POE Oils

POE oils from a severe acid system will smell like dirty diapers.

Severe burn outs create acids and alcohol and moisture.

Waste oil may be disposed through waste recyclers.

POE Oils-WARNINGSynthetic oil will attack many roofing

materials. When servicing equipment mounted on a roof, the roof must be protected from oil spray or spills. Use a plastic covering or tarp to protect the work area.

Wiping up a spill will not stop long term damage to the roofing materials.

* System contains POE oils that absorb moisture faster than current mineral oil.

* Unopened containers have less than 50 ppm/ water.

Special ConsiderationsFor POE Oils

POE Oils

‡ Open containers can absorb 1500 to 2000 ppm/ water.

‡ Keep containers sealed when not in use.

‡ Use reasonable refrigeration practices.

Moisture, POE Oil, and Driers

MOISTURE IS BAD - DRIERSMUST BE REPLACED EVERY

TIME A REFRIGERANTCOMPONENT IS REPLACEDOR THE SYSTEM IS OPENED

FOR SERVICE

Special Considerations

MoistureVacuum pumps will not

completely remove moisture, driers must be replaced every time a refrigerant component is replaced.

Not even a deep vacuum will remove moisture from POE oils!

Time Minutes

PP

M M

ois

ture

Oil Moisture Absorption Rate

100

200

300

Sample Size: 13

237 PPM

129 PPM93 PPM

75 PPM

270 PPM

156 PPM

Filter Change at 60Days Operating

30 PPM

20 PPMExit Copeland Exit-Rack

ManufacturerAt Jobsite At Jobsite

30 Days

75 Days

Discus Compressors/Polyol Ester OilMoisture Content Versus Time

Water Uptake of POE Oil Continuously Exposed to a Humid Atmosphere

0

500

1000

1500

2000

1 2 3 4 5 6 7 8 9Time, Hours

Wate

r C

on

cen

trati

on

, p

pm

Conditions

70°F & 85% Humidity

500 ml of Oil in1 liter open beaker

DRIERS

• Liquid line driers designed for R410A must be used every time a refrigerant component is changed.

• Suction line driers should only be left in a system for a maximum of 72 hours.

DRIERS• Suction line driers must only be used

on the low side of the system. Operating temperatures and pressures may be exceeded if applied on the high side.

• High temperatures will cause the activated alumina in suction line driers to decompose, causing more acid.

Inside the Filter-Drier box you will find this pamphlet.

Refrigerant Safety

• Cylinder is rose colored. (Pink)• Store at 125 degrees or less.• Never charge any refrigerant cylinder

to more than 80 % of its capacity.• R410A boils at -62.9 degrees. 20

degrees less than R-22. More frostbite potential.

R-410A Safety ….continued

• Low toxicity, but can displace oxygen• Heavier than air. Needs ventilation in a confined

space.• Classified as a non- flammable, but can ignite

when mixed with air under pressure.– Do not braze with system under pressure.

• Since pressures are significantly higher, all servicing tools and recovery cylinders must be rated to withstand these pressures.

R-402AR-407BR-507R-407AR-404AR-402BR-408AR-502R-410AR-407C(30-70 Blend)

R-22R-401BR-409AR-401A

R-12

FX40HP80

KLEA-61AZ50

KLEA60FX70/HP62

HP81FX10

CFC-502AZ20

AC900032/134aHCFC-22

MP66FX56

MP-39R-134aCFC-12

0 100

200

300

400

500

Saturation Pressure at 130°F

CAUTIONSR-22 R-410A

TEST

80 /67 - 82

80 / 67 - 95

70 - 47 / 43

70 - 35 / 33

70 - 17 / 15

Suction Dischargepsig psig

Suction Dischargepsig psig

76 223 135 346

78 263 138 405

53 216 97 330

43 198 80 308

28 173 55 274

*Typical Pressures, for example only, pressures will vary with models.

LEAK DETECTION

• Electronic leak detectors must be capable of detecting HFC gases. Halide torches detect chlorine and will not work with HFC refrigerants.

• Fluorescent dyes are not approved for Trane equipment.

RECYCLING AND RECLAMATION

+The Clean Air Act of 1990 requires mandatory recycling and reclamation of all refrigerants.

+Recovery equipment must be compatible with R-410A.

Equipment Differences?

>All of the R-410A products use scroll compressors.

>R-410A has less displacement as a vapor than R-22, requires smaller vapor piping.

>Most products will use 5/16” coils instead of 3/8” and the coils are rated for the higher pressures.

>Pound for pound the charge doesn’t vary greatly from R-22.

EXISTING INSTALLATION• If a R-22 sized suction line must

be used, linear line lengths will be limited to 40 feet and 30 feet vertical change.

*Exception: 1 ton and 4 ton systems must use R-410Aspecified line sizes.

NEW INSTALLATION

• Recommended suction line sizes will typically be one size under current R-22 line sizes.

• Line lengths will remain at 80 feet linear and 60 feet vertical change.

NEW INSTALLATION

• Only matched systems will be allowed. There will be no exceptions at this time.

• Refrigerant lines must be new.

Page 2

Page 3

Page 4

•Sensing bulb location

•NO

•YES

SYSTEM CHARGING• Complete low side charging is not

recommend in any system. It is time consuming, and if the servicer rushes the unit by adding liquid refrigerant, compressor damage could result.

• Rapid low side charging of a scroll, with power off, could result in the scroll flanks sealing axially, preventing rotation. Once the system is equalized, the scroll will start.

SYSTEM CHARGING• The subcooling method is required when charging

TXV systems.

• Charging charts are included in the Service Facts document that come with the outdoor equipment.

• Remember to allow sufficient time for the system to stabilize before adjusting the refrigerant charge.

Charging with R-410A

• In the vapor state a blended refrigerant may fractionate

• Charge with liquid in the low side.– Put vapor into the low side. Use a

metering device

SYSTEM CHARGING

*When charging with liquid on the low side of a system, use a commercial type metering device in the manifold hose. i.e. Chargefaster (CH200) made by Watsco, or equivalent.

Charging by the Subcooling Method

• All of our R-410A systems are TXV metered at this time.

• You must get an accurate temperature reading on the liquid line.– Use an electronic sensor and insulate it.

• Use the charts shipped with the unit.• Allow a lot of time for charging, charge

a little and wait.

Using the Charging Chart

• Measure temperature and pressure at liquid line.

• Use line length & lift to choose which curve to use.

• Plot the intersection of temp. & pressure.• If above the curve, remove refrigerant.• If below, add refrigerant• Wait 20 minutes to stabilize.

(390 PSIG & 115º F)

Sub-Cooling & Superheat Calculation Explained

Use the following chart to show how to calculate Sub-Cooling and Superheat

First chart is a Properly Charged system

Sub-Cooling indicates amount of refrigerant STORED in the condensing unit

Sub-Cooling & Superheat Calculation Explained

Low Sub--Cooling indicates LOW-charge High Sub--Cooling reading indicates

OVER-charge (or possible Liquid Line restriction)

Rule of thumb = 10 - 15 degrees of sub-cooling Manufactures’ usually design to 10 degrees

Lower Heat Pump’s sub-cooling down to 10 - 13 degrees if high head problems occur

Sub-Cooling & Superheat Calculation Explained

Superheat indicates that complete vaporization of liquid refrigerant in the evaporator coil has taken place

Low Superheat means liquid refrigerant is present at or near the outlet of the evaporator Compressor Damage is immanent

High Superheat means liquid is boiling off too soon and could mean evaporator is starved

Indoor Coil Outdoor Coil

High Pressure,High Temperature VaporSaturatedVapor

High Pressure, Sub-cooled Liquid

Low Pres.Liquid

SaturatedVapor

SuperheatedVapor

minus -

LL Pres. to Saturation

LL Temperature

equals =Sub-cooling

Basic Refrigeration CircuitProperly Charged Unit

SL Temperature

SL Pres. To Saturation

equals =Superheat

minus - Sub-cooling & SuperheatCalculation Explained

Sensi

ble

Late

nt

Sensi

ble

Sensi

ble

Late

nt

55

10°45°

76#

98°

10°

220#

108°

Over-Charged System High Sub--Cooling reading indicates excessive

amount of refrigerant in the condenser coil Head pressure reading will be high Saturation temperature will be high Liquid line temperature at or near ambient Unit will use excessive wattage to do the

same amount of work If TXV is working properly, work at indoor coil

will be basically the same as properly charged system and Superheat will be normal

Indoor Coil Outdoor Coil

High Pressure,High Temperature VaporSaturatedVapor

High Pressure, Sub-cooled Liquid

Low Pres.Liquid

SaturatedVapor

SuperheatedVapor

minus -

LL Press. to Saturation

LL Temperature

equals =Sub-cooling

Basic Refrigeration CircuitOver Charged Unit

SL Temperature

SL Pres. To Saturation

equals =Superheat

minus - Sub-cooling & SuperheatCalculation Explained

Sensi

ble

Late

nt

Sensi

ble

Sensi

ble

Late

nt

55

10°45°

76#

118°

17°

316#

135°

Under-Charged System Low Sub--Cooling reading indicates lack of

refrigerant in the condenser coil. Head pressure reading will be low Saturation temperature will be low Liquid line temperature will be high Unit will use excessive wattage due to do

extended run times to do the same work TXV will not work properly, due to lack of

“liquid seal” resulting in capacity loss Superheat will be high - coil starved.

Indoor Coil Outdoor Coil

High Pressure,High Temperature VaporSaturatedVapor

High Pressure, Sub-cooled Liquid

Low Pres.Liquid

SaturatedVapor

SuperheatedVapor

minus -

LL Press. to Saturation

LL Temperature

equals =Sub-cooling

Basic Refrigeration CircuitUnder Charged Unit

SL Temperature

SL Pres. To Saturation

equals =Superheat

minus - Sub-cooling & SuperheatCalculation Explained

Sensi

ble

Late

nt

Sensi

ble

Sensi

ble

Late

nt

68

42°26°

50#

95°

182#

95°

Real Life Charging Procedures-

Expansion Valve Systems First Things First!

Clean coils (indoor and outdoor) Check air filters

Do Air Flow check. Use Engineering Data for reference Humid climates demand it Full unit capacity depends on it

Real Life Charging Procedures

Indoor temp. needs to be between 70º - 80º Run system for 10 minutes to stabilize Check system Superheat

Measure suction line temperature at outdoor unit

Convert suction line pressure to saturation (read directly off of gauges or use pressure-temperature chart)

Suction line temperature minus saturation temperature = System SuperheatSystem Superheat

Nominal range = 15º - 25º, measured @ O.D. unit

Real Life Charging Procedures

You’re now only halfway finished! Next, Check System Sub-coolingSub-cooling

measure the Liquid Line temperature Convert Liquid Line pressure to

saturation (read directly off of gauges or use pressure-temperature chart)

Saturation temperature minus Liquid Line temperature = Sub-coolingSub-cooling

Nominal range = 10º - 15º

What Does All That Mean?

Low SuperheatSuperheat readings indicate Low Airflow

Dirty coils Dirty air filter Wrong blower speed

Faulty metering device, or improper size - too large

Possible overcharge (suspect last)

What Does All That Mean?

High SuperheatSuperheat readings indicate Too much airflow

Wrong blower speed

Faulty metering device, or improper size - too small, improperly adjusted

Power element w/ low or no charge Valves fail shut with no charge in power

element

Possible undercharge (suspect last)

What Does All That Mean?

High Sub-coolingSub-cooling readings indicate Restriction at the...

Liquid Line filter Metering device in the evaporator

Possible overcharge (only if superheat is normal as indicated by above)

Low Sub-coolingSub-cooling readings indicate Undercharge (proven by high superheat

readings) Sub-coolingSub-cooling below 10º indicates low charge Sub-coolingSub-cooling above 15º indicates over-charge

Diagnostics

• Outdoor circuit diagnostics• Indoor circuit diagnostics• Circuit accessories

– Receivers– Accumulators– Filter driers– Sight glasses

If this systems suction pressure were 58PSI (32 ), andthe suction line temperature measured 35 . what wouldthe superheat be? Would it indicate the evaporator to benormal, flooded or starved?

Condenser Evaporator

Liquid Line Metering

Heat Rejection Heat Extraction

Hot Gas Line Suction LineCompressor

Condenser Drier Evaporator

Liquid Line Metering

Heat Rejection Heat Extraction

Hot Gas Line Suction LineCompressor

If this system’s discharge pressure was 200PSI (102 ), and the liquid line temperature leaving the condenser coil was 82 . What would the subcool be? Would it indicate your condenser is normal, flooded or starved?

There are three times to troubleshoot a system!

• On a service call– Most expensive– Reputation on the line– Repairs the most time consuming to

make.

• On start up– Time consuming checking

temperatures and pressures– Must figure this time into job.– Repairs made now can save money in

the long run

• During bidding process– Customer pays bill– Customer is made aware of possible

expenses up front– You come off as one who knows more

than the competition

Internal Parts

Process Tube

Bulb Leak

Power Head

Diaphragm

Equalizing Line

Product Overheating

Other Monitored TXV Failures

• Dead Element

• Super Heat Setting

• Field Disassembled

• Field Damage

• Internal Diaphragm

• Foreign Matter

Sensing Bulb Cut

Overheating

Overheating

Fatigued Tubing

No Failure36%

Incorrect Setting

10%Broken Cap Tub

19%

Overheated 11%

Leak-Bulb

Foreign Matter

Leak-Charging Tip 9%

Disassembledin Field 2%

Dead Element 1%

Incorrect Assembly1%

Material Defect1 Unit

Leak-Element Cap Tube1%

Misc. Field Damage1%

Stuck contacts 13.0%

Coil open 4.5%

Noisy 6.5%

Stuck plunger 4.5%

Misc. 11.5%

40% Relay Issues

No Fault 60%

• Uses sealed circuit board relays

• Uses same terminals as previous electromechanical relay

• Has a surge protector to prevent electrical transient damage (Voltage Spikes)

• Replaces old relay in the field

A

B

6

T

4

Low Voltage Relay

Fan Relay Terminals

Trane/AmStdTraining CD-Program

Publication #34-3416-01Mechanical Refrigeration

TroubleshootingR-22/R-410A

#1 Reason To Buy A Warranty

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