halton hvac handbook chilled bean design guide
TRANSCRIPT
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
1/44
Care for Indoor Air
Halton- Chilled Beam Design Guide
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
2/44
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
3/443
1. Chilled beam system 5
2. Target definition 6
3. Active chilled beams
3.1 Active chilled beam system 7
3.2 Chilled beam system design 8
3.3 System design strategies 9
3.4 Design elements 10
3.5 Chilled beam model selection 12
3.6 Adaptable chilled beam concepts 14
3.7 Chilled beam orientation and ventilation arrangements 22
3.8 Operation range specification 24
3.9 Product selection 25
3.10 Indoor climate conditions design 26
3.11 Management of room conditions 27
3.12 Case study 30
4. Passive chilled beams
4.1 Passive chilled beam system 31
4.2 Chilled beam system design 32
4.3 Chilled beam model selection 33
4.4 Chilled beam orientation and ventilation arrangements 35
4.5 Operation range definition 37
4.6 Pre-selection and selection 38
4.7 Design of indoor climate conditions 40
4.8 Management of room conditions 48
5. Customised service beams
5.1 Luminaires and other integrated technical services 42
Contents Chilled Beam Design Guide
Contents
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
4/444
Chilled beam system
Haltons chilled beam system is an air conditioning system
for cooling, heating, and ventilation in spaces where good
indoor climate and individual space control are appreciated.
A chilled beam system provides comfortable thermal
conditions with quiet and energy-efficient operation.
The system can be realised with active or passive chilled
beams, integrated multi-service chilled beams, or
bulkhead-installed horizontal induction units.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
5/445
Chilled beam system
Haltons chilled beam system is an air conditioning
system for cooling, heating, and ventilation in spaces
where good indoor climate and individual space control
are appreciated.
A chilled beam system provides comfortable thermalconditions with quiet and energy-efficient operation.
The system can be realized with active or passive chilled
beams, integrated multi-service chilled beams, or
bulkhead-installed horizontal induction units.
Chilled beam system design
A chilled beam system provides excellent indoor climate
conditions and cost-efficient life-cycle costs when realization
is managed properly from design to use of the building,
covering:
Definition of targets
System design
Product selection
Room control
Ductwork and pipework design
Central systems design
Eventual free cooling / heat pump applications
Installation and commissioning
Verification of indoor climate conditions
Flexibility throughout the lifetime of the building
Modern office buildings are designed to allow flexibility inuse of the spaces to meet the requirements of even high
churn rates (percentage of people moving in the building
in one year).
The air conditioning system design can be carried out
according to different strategies, for more limited to full
flexibility:
Traditional design
AdaptableClimateconcept
Flexibility requirements can affect the design, logistics in
transport and at the site, and the tasks required when room
layout or the use of space changes.
Halton chilled beams
Haltons chilled beam range includes many different types
and models:
Adaptable active chilled beams (ACC, ACE) for suspended-
ceiling and exposed installation
Active chilled beams for suspended-ceiling installation
(ABC, ABD)
Active chilled beams for exposed installation (ABE, ABH)
Passive chilled beams for suspended-ceiling installation
(APA)
Passive chilled beams for exposed suspended-ceiling
installation (APT)
Customized active and passive service beams for both
suspended-ceiling and exposed installations Compact, bulkhead-installed induction units with uni-
directional horizontal air supply (AHH)
Applications for different chilled beam types
Active chilled beams. Active chilled beams are well suited
to private and public office buildings, health care facilities,
and hotel buildings in new construction as well as
refurbishment projects.
Active chilled beams are especially suitable for landscape
and cell offices, patient care spaces, and hotel guest rooms.
Adaptable active chilled beams are ideal for flexible office
spaces, where office layouts are changed frequently and
spaces are shifted often between office rooms and team,
project and meeting rooms.
Passive chilled beams. Passive chilled beams are used
in the same applications as active chilled beams. There
are, however, specific conditions favoring passive beam
installations:
Applications where ventilation rates are relatively high
e.g., 0.7 0.9 cfm/ft2
Refurbishment projects where the existing ventilationsystem is to be preserved for the most part
Where ventilation is realized using a separate system
e.g., an under-floor air distribution system
Chilled beams with uni-directional air supply.Units with
uni-directional air supply are used in spaces where most of
the ceiling is left free of room unit installations. The units
can be standard chilled beam units designed for
performance with uni-directional supply or units dedicated
to uni-directional air supply in exposed or bulkhead
installations.
Customized service beams.Active and passive
customized service chilled beams are feasible for
refurbishment projects in office and other public buildings.
The benefits of customized service beam systems are:
Effective installation of technical services and good total
quality of installations due to off-site manufacturing and
short construction process
Selection of exposed or ceiling-integrated beams on the
basis of a feasibility study for the building by consulting
engineers
The ability to create aesthetic interior
1. Chilled beam system
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
6/446
Target definition
2. Target definition
When the main targets for system operation and performance are set, indoor climate target values are specified.
One of the key goals in designing good indoor climate conditions is to adjust the cooling and heating capacity to the
level that meets both optimal comfort and energy-efficiency targets.
In addition, module sizing and flexibility requirements are important factors influencing both design decisions and
life-cycle cost management for the building. It is also important to take into account national and international
standards and building codes.
Indoor climate target levels according to CEN report 1752, on maximum values for thermal conditions.
Indoor climate factor Classification
Unit A B C
Operative temperature Winter F 71 2 71 3.5 71 5
Operative temperature Summer F 76 2 76 3 76 4Vertical temperature gradient 0.3 ft / 0.3 ft F 3 5 7
Mean air velocity Winter fpm 30 35 40
Mean air velocity Summer fpm 35 43 50
Sound pressure level Office rooms NC 30 33 35
Sound pressure level Landscape offices NC 35 38 40
Ventilation rate Office rooms cfm/ft2 0.45 0.3 0.2
Ventilation rate Landscape offices cfm/ft2 0.35 0.25 0.15
Ventilation rate Meeting rooms cfm/ft2 1.3 0.9 0.5
Design assumptions Occupancy:
Clothing:
office rooms 100 ft2per person
landscape offices 70 ft2per person
meeting rooms 50 ft2per person
0.5 clo summer; 1.0 clo winter
Indoor climate design conditions:
Thermal conditions as specified in national or
international standards or classifications
Room air temperature or operative temperature
Mean room air velocity or draught rate (DR)
Internal surface temperatures and radiant
asymmetry
Air quality criteria as specified in national or
international standards or classifications air qualityoften is indicated in terms of:
Outdoor air flow rate
CO2concentration
Sound level requirement is expressed as:
Noise Criterion NC
Sound pressure level Lp(A)
Typical space design data
Room and module dimensions
Space usage, internal load and occupancy levels
Window and wall types, and solar shading
Life cycle costs:
Target system investment cost level ($/ft2)
Energy-efficiency targets' levels can be expressed
as specific level of consumption of heating energy
and air conditioning and electric power (fan power).
The building should be classified according to these
consumption levels.
Maintenance level targets indicate:
Predicted service intervals
Labor demand
Accessibility of service points
Need to replace parts / replacement interval
(valve, filter, motor, and other parts.)
Flexibility for change:
Flexibility requirements can be characterized with
the required tasks when layout or the use of space
changes:
Need for office / meeting room changes
Need to relocate internal walls
Need for installation / reconnection of terminal
units or control units
Adjustment of airflow rates
Adjustment of water flow rates
Other adjustments (e.g. personal requirements)
Order delivery chain:
Targets for order delivery indicate the versatility of
the terminal unit in terms of their models, sizes and
operation parameters.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
7/447
Active Chilled Beams
3. Active chilled beams
3.1 Active chilled beam systemThe chilled beam system is an air/water system for high-
temperature cooling and low-temperature heating that
utilizes the excellent heat transfer properties of water
and provides a good indoor climate energy-efficiently.
Typically, a chilled beam system is realized as a dedicated
outdoor air system with sufficient airflow rates to ensure
good indoor air quality.
Either the system employs a four-pipe system or a
separate perimeter heating system is used. Even two-
pipe application with system changeover between
cooling and heating is used.
Operation of the systemChilled beam systems are designed to use the dry
cooling principle, operating in conditions where
condensation is prevented by control applications.
Chilled water can be produced by a dedicated chiller only
for chilled beams or a common chiller for air handling units
with a separate, flow-water-temperature-controlled loop for
chilled beams, preferably connected via a buffer tank.
Space temperature control is realized with variable water
flow control using either on-off or proportional control
principle.
Ventilation
Ventilation using active chilled beams is an efficient mixing
ventilation application that results in uniform air quality.
Supply air is discharged into the space through linear slots
on either both sides or only one side of the chilled beam.
Horizontal induction units have grilles for horizontal air
supply. In demand-based ventilation applications, supply
airflow can be increased by means of an integrated
diffuser without affecting the heat transfer of the chilled
beam.
Cooling
Active chilled beams use the primary air to induce and
recirculate the room air through the heat exchanger of
the unit, resulting in high cooling capacities and excellent
thermal conditions in the space. High-temperature
cooling enables the use of various free-cooling sources,like outdoor air, sea water and geothermal energy etc.
Heating
Integration of heating into chilled beams is
recommended when the specific heating capacity of the
chilled beam units is reasonably low (155 260 Btuh/ft),
and the low heat transmission through the windows
prevents a downdraught under the window.
Low-temperature heating enables the use of various
waste-heat sources. Alternatively to hydronic heating,
electric heating can be integrated in chilled beam units.
Schematic diagram of a chilled beam system with both cooling and heating functions.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
8/448
Chilled beam system design
3.2 Chilled beam system design
A chilled beam system can be designed to fulfill requirements for sustainable, energy-efficient buildings that provide
flexible use of space and a healthy and productive indoor climate. A chilled beam system can realize excellent indoor
climate conditions in terms of thermal and acoustic properties throughout wide operation ranges and in many
installation scenarios.
There are several choices to be made, each having an influence on the performance, investments, operation, and
maintenance costs. The tables below present the range of variation of the main design characteristics and typical
ranges of operation for a chilled beam system.
MAIN CHARACTERISTICS FOR CHILLED BEAM SYSTEM EVALUATION
Indoor climate conditions
AdaptableClimateconcept Traditional concept
Good indoor climate conditions and efficient, practical operation
with highly realistic design data for the building's whole life cycle.
Reservations for performance at extreme capacity levels with high
safety margins.
Use of the space
Changes in use of the space and layout changes with marginal
churn costs.
Optimized performance and unit cost for individual spaces with
limitations in flexibility.
Relatively high churn costs.
Efficiency of logistics
Effective design, installation, and commissioning processes;
streamlined logistics with a uniform product range.
Need for individual product identification in design, ordering,
delivery, and installation.
Life-cycle performance
Higher investments in more efficient chilled beams (greater
difference), enabling savings in pipework central units and lower
operation costs.
Lower investment costs for chilled beams and higher total
investment and operating costs.
TYPICAL INPUT VALUES AND OPERATION RANGES
Room temperature, summer 73 77 F
Room temperature, winter 68 72 F
Supply air temperature 61 66 F
Water inlet temperature, cooling 57 61 F
Water inlet temperature, heating 95 104 F
Target duct pressure level 0.3 0.5 in WC
Target water flow rate, cooling 0.32 1.6 gpm
Target water flow rate, heating 0.16 0.65 gpm
Noise criteria NC 30
Outdoor air flow rate / floor area, offices 0.33 0.55 cfm/ft2
Outdoor air flow rate / floor area, meeting : 0.33 0.9 cfm/ft2
Outdoor air flow rate / effective unit length 3.6 ... 9 cfm/ft
Additional air flow rate in meeting rooms 0 ... 53 cfm per unit
Cooling capacity / floor area 25 Btuh/ft2 38 Btuh/ft2*
Cooling capacity / effective unit length 250 Btuh/ft 400 Btuh/ft *
Heating capacity / floor area 4 Btuh/ft2 19 Btuh/ft2**
Heating capacity / effective unit length 150 Btuh/ft 200 Btuh/ft **
Note * It is reasonable to study the room air velocity conditions carefully
Note ** It is reasonable to study the thermal conditions carefully
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
9/449
System design strategies
When a chilled beam system is designed and chilled beams are selected, there are several angles to be considered.
The main target is to achieve excellent indoor climate conditions in spaces for the whole life cycle of the building,
even if there is a continuous need to make changes in the space usage or layout. Through designing and selecting
chilled beams according to an adaptable strategy, this target can be achieved.
3.3 System design strategies
Adaptable system design
Adaptable system selection strategy provides benefits
to the facility owner, who can modify spaces more
quickly and with less cost over the facility's lifetime.
Thermal condition management using Halton Velocity
Control (HVC) and air quality control using Halton Air
Quality (HAQ) provide continuously good indoor
climate conditions.
The design and installation teams can also benefit,
because changes in the use or size of spaces during
System design
strategyAdaptableClimateconcept Traditional concept
Indoor climate
conditions
Room air temperature 754 3.5 F 754 3.5 FRoom air velocity ... 50 fpm ...50 fpm
... 60 fpm temporarily during peak loadsRoom air quality
CO2- concentration
Ventilation rate
900 ppm
0.31 cfm/ft2
(variable flow in meeting rooms)
1000 ppm
0.375 cfm/ft2
(constant airflow in meeting rooms, or separate
variable airflow application)Cooling capacity
levels
2025 Btuh/ft2 2040 Btuh/ft2
Heating capacity 612 Btuh/ft2 620 Btuh/ft2
Adaptable
performance
Halton Velocity Control (HVC) is designed at normal
position (2).
Adjustment in throttle (1) and full (3) position, when
required.
Adjustment of constant airflow rates and using Halton
Air Quality (HAQ) control.
Adaptation by increasing the number of terminal
units.
Chilled beam
positioning
Always perpendicular to perimeter wall Either parallel or perpendicular to perimeter wall
Life cycle costs
Flexibility Full flexibility in layout and application changes: no
installation work during changes.
Churn costs of 100130 $/ft2.
Limited flexibility in layout and for changes in
operation conditions.
Churn costs of 7501000 $/ft2.Product cost Some extra cost for flexibil ity in room units, zones,
and central system costs.
Basic investment.
Additional installations for variable flow application in
meeting rooms.Focus in product
selection
Nozzle size, length, and effective length that are the
same using adaptable active chilled beams.
Various nozzle sizes, lengths, and effective lengths
according requirements using basic active chilled
beams.
Water flow control and adjustment valves which are
selected project- specifically and installed on siteChanges in space use
and layout in the design
and installation process
No effect of changes in use or size of space on chilled
beam selection
Eventual reselection of chilled beams after significant
changes of use or size of the spaces
Commissioning Adjustment of chilled beams on site; no traditional
commissioning needed.
Constant-pressure control dampers in zones allow
quick airflow rate adjustments and variable airflow in
meeting rooms.
Maximum limit flow valves allow quick adjustment of
water flow rates without balancing need.
Traditional commissioning comprising
manual balancing of airflow rates using adjustment
dampers
manual balancing of water flow rates using
adjustment valves
Note: Typical design values. Check case by case.
the design and construction process do not influence
the beam selection.
Traditional system design
Designing and selecting chilled beams according to
traditional strategy allows indoor climate targets to
be met in the design conditions, but future changes in
use or layout may influence the products
performance.
This strategy results in a lower investment cost, but
changes during operation are more costly.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
10/4410
Design elements
A chilled beam system can realize excellent indoor climate conditions in terms of thermal, air quality, and acoustic
conditions within wide ranges of operation and in various installation cases. Operation should, however, be
designed with conditions in the occupied zone in all seasons (winter, summer, and intermediate season) taken into
account. For the best result, the following technical issues should be considered also.
3.4. Design elements
Ventilation and air diffusion using chilled beams
Primary air from the nozzles (3.5 9 cfm/ft) induces
3 5 times the room air (depending on chilled
beam type and operating conditions).
A total airflow rate of 10 40 cfm/ft is discharged
from one/two slots into the space.
Make sure that airflow rates can be realized at actual
chamber pressure levels.
Minimum supply chamber pressure is 0.2 0.3 in
WC to ensure the correct supply air jet throw
pattern.
Check that the required throttle for balancing can be
achieved with the adjustment damper at an
acceptable sound level.
The supply airflow rate is high enough to remove
internal humidity loads.
The supply air jet should stay attached to the ceiling
(Coanda effect) and not fall directly into the occupied
zone.
Thermal loads in the occupied zone may influence
the air jet direction and air distribution in the
occupied zone.
Analyze supply jet interaction with convective flows
caused by a cold or warm window surface to ensure
that it doesn't create a draught risk.
When already detached from the ceiling, jets of two
parallel chilled beams should not collide at a velocity
level that results in a draught.
The increase of airflow rate according to demand
should not have a significant effect on the coil
cooling capacity.
Cooling using chilled beams
The thermal properties of the external walls and
window construction should be appropriate.
The required cooling capacities should be max.
20 25 Btuh/ft2.
Chilled beam capacities (250 360 Btuh/ft) match
supply airflow rates (3 9 cfm/ft) to provide good
air distribution and draught-free conditions in the
occupied zone.
Water flow rates and pressure drops of chilled
beams are in line with chilled water pipe work
design and pumping cost target levels.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
11/4411
Design elements
Heating
Proper system operation cannot be achieved by over-
dimensioning the heating capacities. In a modern
office building, 8 15 Btuh/ft2of floor area is typically
sufficient heating capacity.
The heating capacity of active beams is dependenton the primary airflow rate. This is why ventilation
shall be in operation when heating is required.
The heating capacity of active beams is typically
160 260 Btuh/ft, and the inlet water temperature
should be 95 115 F to create sufficient mixing
between the supply air and room air.
Both window draught due to radiation and
downward convective air movement during cold
seasons need to be eliminated.
An efficient control system is used. It isrecommended to have room air temperature
measurement integrated into a chilled beam, with
heating control based on the room air temperature
near the ceiling.
Operation case study: Chilled beams parallel to the
perimeter wall
In this type of installation, it is especially important to
have windows with adequate thermal properties for
avoiding excessively high room air velocities inintermediate seasons.
This study was performed using computational fluid
dynamics (CFD) software. Air velocity is higher than
50 fpm in the green areas.
The images present the room air velocities in the
same space in three seasons: summer (1), spring (2)
and winter (3).
1
2
3
The images present the room air velocities in the same space in three seasons: summer (1), spring (2) and winter (3).
Temperature conversion
17.7 C = 64 F
24 C = 75 F
28 C = 82 F
17 C = 62.6 F
20.2 C = 68 F
22 C = 71.6 F13 C = 55.4 F
22 C = 71.6 F
25.4 C = 77.7 F
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
12/4412
Active chilled beam model selection
The appropriate active chilled beam model is selected by
taking into account the following factors:
Architectural design
Preferred appearance
Desire for exposed installation or a solution integrated
into a suspended ceiling
Adaptation to the ceiling
Positioning with respect to light fittings Integration of light fittings
Room design grid dimensions and available space
Requirements for flexibility and eventual partition
wall locations
Cooling capacity and ventilation rate requirements
Building services integrated into chilled beams:
Light fittings, controls, sensors, detectors, and cabling
Adaptable active chilled beams are selected when the
requirements for cooling capacities and ventilation rates need
to be adjusted along with the space layout changes or when
variable airflow is used for demand based ventilation.
3.5. Active chilled beam model selection
Active chilled beams in suspended ceiling installation
Customized service beam.
Active chilled beam in wall installation.
Active chilled beam in exposed installation
Active chilled beam in suspended ceiling installation
Active chilled beam in bulkhead installation or
in exposed installation.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
13/4413
Active chilled beam model selection
Active chilled beams in exposed installation
Active chilled beams in wall installation
Customized service beams in exposed installation.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
14/4414
Adaptable chilled beam concepts
Halton AdaptableClimatechilled beamsoffer unique flexibility from design through use. Their operation adapts easily
to changes in space usage, layout, or user requirements throughout the buildings life cycle.
Good indoor climate conditions are maintained with high energy-efficiency when an open-plan office is changed into
cellular offices or meeting rooms.
Chilled beams adapt thermal conditions to meet individual requirements, also in open-plan offices. Thus indoor
climate conditions are optimal in all usage situations throughout the buildings life cycle.
3.6. Adaptable chilled beam concepts
Benefits of the Halton adaptable chilled beams:
Wide operation range simplifies design and
specification
Good thermal comfort and indoor air quality
Adjustable air flow rates
Air velocity management
Enhanced flexibility
Free location of offices and meeting rooms
Identical look of units for different
spaces
Air flow control that can be installed as
needed
Improved logistics
Smooth order-to-delivery process
Effective on-site handling
Features:
Primary air flow rate adjustment of 0.3 to 0.9 cfm/ft2
in layout change from office room to meeting room
using Halton Air Quality control (the air flow control
does not affect the coil capacity, and thus over-
chilling is avoided)
Ability to achieve individual desired velocity
conditions in the occupied zone even when partition
walls are repositioned, by adapting the operation
using Halton Velocity Control
Integrated control and max. flow limiter valves for
cooling and heating capacity allowing reset without
influencing the water flows of other chilled beams
(optional)
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
15/4415
Adaptable chilled beam concepts
Primary airflow rate
Room Space type HVC position Nozzles qv1
HAQ qv2
Total qv1
+ qv2
Total qv1
+ qv2
left right cfm cfm cfm cfm/ft2
1, 2, 3 Office 3 1 32 11 43 0.48
4 Meeting room 2 2 32 0 ... 53 32 ... 85 0.9
Management of ventilation rates using
Halton Air Quality (HAQ) control
The air flow rate of the chilled beam is dependent on
Effective length, Leff
Chilled beam chamber pressure, DPm
Nozzle size, Dnoz
Halton Air Quality control unit adjustment position,
AQ
The chamber pressure is adjusted by changing the
position (a) of the airflow adjustment damper to match
available duct pressure at the room branch.
Four nozzle sizes are available, to enable attaining the
minimum supply air flow rate of the chilled beam at
the set pressure level in a typical room module.
There is no need to change or plug nozzles of the
chilled beam.
Halton Air Quality control allows increasing the chilled
beam airflow rate to meet the ventilation requirements
of spaces such as:
office spaces: 0.3 0.6 cfm/ft2
meeting rooms: 0.7 0.9 cfm/ft2
Air flow control
The ventilation requirements of meeting and team
rooms vary greatly according to the occupancy level.
Demand-based ventilation control using, e.g., CO2
sensors, contributes to a highly energy-efficient
operation.
In addition to manual adjustment damper operation,
the HAQ damper can be equipped with an actuator
controlled by a room controller.
Factors influencing an active chilled beams air flow rate.
Office rooms.
Meeting room.
By integrating the airflow control into the chilled beam
unit, flexibility in use of the space is ensured.
When rooms with constant and variable airflow rates
are both served by the same distribution ductwork,
constant pressure conditions are needed to guarantee
the designed airflow rates.
See the section Constant-pressure ductwork for
efficiency for more information.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
16/4416
Halton ACE with air quality control.The Halton Air
Quality control unit is on the top of the chilled beam,
supplying air upward. It is recommended to position
the beam at a minimum distance of 2 ft from the wall
and 4 in from the ceiling.
The Halton Air Quality control unit is adjusted manually
or, alternatively, controlled by an actuator connected to
a room controller.
The HAQ unit can be retrofitted later as required. Also
the actuator can be mounted later, when changes in
room layout are implemented.
Total airflow rate of the chilled beam unit can be 4 to
20 cfm/ft when equipped with HAQ control.
The Halton Air Quality control unit does not increase
the length of the chilled beam.
Halton ACC with air quality control. In the Halton ACC
solution, the air quality control unit is at the opposite
end of the unit from the supply air connection. Thethrow pattern of the air quality control unit is
bi-directional like that of the chilled beam.
The effective length of a chilled beam equipped with
air quality control unit (either manual or motorized
version) is 2 ft shorter than the total length. The look
of the Halton ACC unit is identical to that of the ABC
chilled beam without HAQ unit.
Halton ACE with air quality control in a meeting room.
Adaptable chilled beam concepts
Halton ACC with air quality control in a meeting room.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
17/4417
Adaptable chilled beam concepts
Management of room conditions using
Halton Velocity Control (HVC)
Halton Velocity Control is used for adjusting room air
velocity conditions either when room layout changes
(e.g., in cases where the partition wall is located near
the chilled beam) or when local, individual velocity
conditions need to be altered.
Halton Velocity Control does not affect the primary
supply air rate, but it does have a slight effect on the
cooling and heating capacities of the unit. The
capacities and velocities can be studied using the HIT
Design software.
It is recommended to design the chilled beam in the
normal position in order to allow both minimization
(throttle) and maximization (full) functions later in the
buildings life cycle.
Halton Velocity Control dampers are divided into
sections to enable the desired adjustment of velocity
conditions in different parts of the occupied zone.
Depending on the length of the beam, optimal lengths
of HVC damper modules are used as follows:
ABC or ACC 1 ft , 1 ft 8 in, and 2 ft 8 in
ABE or ACE 1 ft, 2 ft, and 2 ft 8 in
Halton Velocity Control provides manual velocity adjustment on both
sides of the chilled beam, with three positions: 1 = throttle position, 2= normal position, and 3 = boost position.
Adjustment of local velocity conditions is possible also in an
open-plan office with Halton Velocity Control.
Partition wall located close to the chilled beam. Halton
Velocity Control is adjusted to position 1 on one side and
position 3 on the other.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
18/4418
Adaptable chilled beam concepts
Halton Velocity Control is available for both exposed
and ceiling-installed chilled beams.
Halton Velocity Control in boost (3) and throttle (1) position in a
Halton ACC chilled beam.
Halton Velocity Control in boost (3) and throttle (1) position in a
Halton ACE chilled beam.
Case Study
Flexibility for layout changes can be designed in with the HVC and HAQ concepts. Chilled beam installation adapts
to different room sizes and layout, providing required capacities and maintaining good comfort level.
Primary airflow rate
Room Space type HVC position Nozzles qv1
HAQ qv2
Total qv1
+ qv2
Total qv1
+ qv2
left right cfm cfm cfm cfm/ft2
1 Office 3 1 32 11 43 0.48
2 Office 3 3 32 32 64 0.48
3/Unit A Office 1 3 32 0 32 0.48
3/Unit B Office 3 1 32 0 32 0.48
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
19/4419
Constant-Pressure Air Distribution System
Constant-pressure ductwork for efficiency
In traditional active chilled beam systems, the ductwork
is a proportionally balanced constant-air-flow distribution
system. However, there are reasons it is beneficial or
otherwise reasonable to arrange the airflow
management using active constant-pressure control
dampers. Among these are that
chilled beams with pressure-dependent variable flow
and constant flow are combined in the same
ductwork sections and proper operation conditions
are ensured
frequent individual air flow adjustments of chilled
beam units can be made without the need to balance
the ductwork
pressure control dampers allow zone ventilation
operation hours locally, contributing to energy
conservation in office buildings where tenants office
hours tend to differ, for example
Adaptable chilled beam concepts
Combined pressure-dependent variable flow and constant flow.
Ductwork is divided into constant-pressure zones,
allowing individual adjustment of the air flow rates of
each room and continuous air flow control according to
demand in meeting rooms.
The ductwork is sized using low velocities (< 1200
fpm), taking into account the predicted max. flow rate
in order to minimize pressure losses within the zone
and to maintain the desired air flow accuracy and meet
cooling capacity requirements.
Ductwork balancing is not needed in constant-pressure
duct systems when unitary airflow rates are adjusted
(e.g., for office room space changes). Even constant
airflow rates of office rooms can be integrated into the
same ductwork as variable air flow rate control for
meeting rooms.
Typically, the use of units that are similar (in length or
nozzle type), along with individual adjustment of airflow
rates, allows effective commissioning of the system.
Fan pressure control
Fan speed control is typically used when variable flow
is required. In small and symmetric low-velocity
ductwork, the need for zone dampers is not evident,
but larger duct systems shall be divided into sections,
where duct pressure is kept constant by means of zone
dampers.
Adaptation to the variable operation conditions of a
variable flow system can be realized with variable-speed
drives controlled by frequency converters. The
target is to maintain a duct pressure level that is as low
as possible in order to save on fan power consumption.
The pressure controller maintains a constant or
optimized pressure level in the ductwork using a
pressure sensor as feedback. The sensor measures the
static pressure relative to prevailing pressure in the
building.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
20/44
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
21/4421
Zone balance arrangements
When in the zone there are both units with constant
and units with variable flows, the exhaust is liable to
pressure deviations due to higher pressure losses in
the main branch duct and lack of regaining static
pressure. The air flow balance in spaces in meeting
rooms with variable flow can be realized in different
ways:
Ducted exhaust using a variable flow control damper
Continuous balanced ducted exhaust for constant
flow
Transfer air via a grille to the corridor
Common zone exhaust tracking the variable
common supply airflow
Transfer air via a grille to the corridor
Common zone exhaust tracking the common
variable supply flow
Adaptable chilled beam concepts
Combination of ducted constant airflow exhaust and variable transfer
to common exhaust.
Ducted variable airflow exhaust using variable airflow control
damper.
Transfer air from spaces to common exhaust.
The common exhaust can take care of the air exhaust
of meeting rooms and eventual open office areas.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
22/4422
Chilled beam orientation and ventilation arrangements
3.7. Chilled beam orientation and ventilation arrangements
Chilled beams can be installed either perpendicularly or parallel to the perimeter wall. However, perpendicular
installation is recommended, as occupied zone velocities are thus lowest in all seasons. When chilled beams are
installed parallel to the wall, intermediate-season conditions (cold window surface and internal heat loads) should be
analyzed. Otherwise, cool supply air with a cold window can easily create increased velocities under windows.
Perpendicular installation of chilled beams.
Parallel installation of chilled beams.
Selection of active chilled beam orientation Indoor climate conditions
Capacity per chilled beam unit
Residual velocities for occupied zone
Supply air jet interaction with convective flows
Suitability for room module dimensions
Suitability in view of lighting fixture locations Flexibility for layout changes
Minimum recommended distance between parallel
beams
Minimum recommended distance between chilled
beam and wall/ceiling
Sidewall installation of chilled beams.
Bulkhead installation of horizontal induction units.
Sidewall installations of chilled beams in a hotel guest room. Bulkhead installation of horizontal induction units in a hotel guest
room.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
23/4423
Chilled beam orientation and ventilation arrangements
Exposed installation above a work area:
symmetric throw pattern.
Exposed installation close to wall:
asymmetric throw pattern.
Selection of active chilled beam air arrangements
Active chilled beams should be positioned above workspaces to ensure comfortable velocity conditions. If the
chilled beam is positioned close to a wall, an asymmetrical throw pattern is recommended. Minimum installation
distances from walls and between parallel chilled beams are presented in the product data sheets.
Exhaust air units have minor importance to the solutions operation.
Suspended-ceiling installation above a work area: symmetric
throw pattern.
Wall installation in hotel guest room.
Bulkhead installation in hotel guest room.
Bi-directional air supply
Perpendicular to exterior wall in offices (preferable),
above the work area
Parallel to exterior wall above work area
Perimeter installation, with uni-directional supply
Corridor installation limited application, depending
on work area location and providing bi-directional
supply horizontally and downward
Uni-directional air supply
Hotel guest rooms preferably above bed (above
window as another option)
Patient ward rooms preferably above bed either
along side walls or parallel to exterior walls
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
24/4424
Operation range specification
3.8. Operation range specification
A chilled beam systems operation range is determined on the basis of representative rooms. The selected rooms
are studied to determine cooling and heating loads via dynamic energy simulation software. After assessment of
load patterns in the representative rooms, chilled beam operation parameters are set. The design target values can
be verified by a full-scale mock-up or computational fluid dynamics (CFD) simulation.
Typical input values and operation ranges (extreme target values in brackets)
Room temperature for cooling 73 77 F
Room temperature for heating 68 72 F
Supply air temperature for cooling 61 66 F
Supply air temperature for heating 61 66 F
Water inlet temperature for cooling 57 61 F
Water inlet temperature for heating 95 113 F
Target duct pressure level for cooling 0.3 0.5 inWC
Target water flow rate for cooling 0.32 1.6 gpm
Target water flow rate for heating 0.16 0.65 gpm
Outdoor air flow rate per unit floor area Offices: 0.33 0.55 cfm/ft2, meeting rooms: 0.33 0.9 (1.1) cfm/ft2
Outdoor air flow rate over effective length 3.6 ... 9 cfm/ft
Cooling capacity per unit floor area 25 (38) Btuh/ft2
Cooling capacity / beams effective length 250 (400) Btuh/ft
Heating capacity per unit floor area 4 (19) Btuh/ft2
Heating capacity / beams effective length 150 (250) Btuh/ft
Comfort / PMV -0.5 ... +0.5
Draught rate (DR) < 15%
Average room air velocity Cooling: 45 fpm
Heating: 35 fpm
Definition of design conditions and operation
parameters
Ventilation rates in spaces as rate per floor area
(cfm/ft2)
Ventilation rate in spaces as rate per person (cfm/
person)
Cooling capacity demand in spaces, in Btuh/ft2, and
actual breakdown of loads Heating capacity demand in spaces, in Btuh/ft2, and
actual breakdown of loads
Model rooms and operational parameters
Room temperature
Supply air temperature
Water inlet temperature
Target duct pressure level
Target water flow rate
Maximum sound pressure levelVerification of target design values with full-scale mock-up and CFDsimulation
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
25/4425
Product selection
1. Design data in cooling
Insert the supply air flow rate and temperature
Specify the temperature difference between the
inlet and outlet water of the beam, or, optionally,
insert the inlet water temperature and target water
flow rate.
Calculate the coil capacity using HIT Design, and
compare the coil capacity against the requirement.
Note the capacities transferred by the coil and
primary air.
2. Chilled beam location and velocity control
adjustment
The location and number of chilled beams are
specified (also, asymmetric positioning is possible).
The HVC positions are set to allow adjusting the
throw pattern in the space and providing the
required velocity conditions in the occupied zone.
To provide adaptability to load variations, use
velocity control (HVC) position 2 (normal position).
3. Air quality control adjustment
Set the HAQ airflow rate to match the required
room airflow rate.
HAQ control can be used to adjust the airflow rate
at a specified duct pressure level.
4. Space results / unit performance Check the operation parameters against system
operation conditions to verify that the operation
parameters correspond to those of the system.
5. Design data in heating
Analysis is as in the cooling case.
6. Space results / unit performance in heating
Analysis is as in the cooling case.
Design data window in Halton HIT Design selection.
Room dimensions, occupied zone, and design criteria are specified in
the Room window in Halton HIT Design.
1, 5 2
3
4, 6
3.9. Product selection
Make your design process more efficient with the Halton HIT Design software design tool. Halton HIT Design
enables product selection and performance simulation for the product(s) that addresses, e.g., air velocity, cooling
and heating capacity, throw pattern, and sound level.
Calculate the cooling and heating capacity of the selected chilled beam units by studying chilled beam performance
in the chosen model rooms defined by yourself using desired operation parameters.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
26/4426
Indoor climate conditions design
4.2 m
4.0 m
v3
Study the supply air throw pattern properties and
room air velocities (in design case)
Room air velocities in occupied zone within set limits
(non-isothermal and isothermal cases)
Temperature difference between air jet and room air
Distance at which the jet detaches from the
ceiling (Ld)
Pressure loss lower than the available pressure in
the duct (check that the noise level is within the
limits set) Adjustability of the air flow rate
In cases involving several units; check the impact of
jet interaction on occupied zone boundary velocities
(refer to Lmin
in the leaflet's quick selection table).
3.10. Indoor climate conditions design
Simultaneously with the performance values, verify also that predicted the room conditions are acceptable,
providing efficient air distribution but eliminating draught risks.
Check supply air throw pattern in heating
Simultaneously with the performance values, verify
also that the predicted room conditions are
acceptable, providing efficient air distribution:
Supply air throw pattern and room air velocities (HVC
position as in cooling)
Supply jet adequately reaching occupied zone level
Flow water temperature within recommended range Heating capacity
Impact of the HVC arrangement
Impact of the HAQ arrangement
Study optional room modules
Unit pressure drop (keep at the same level as
before)
Operation with optional room cooling load levels /
room usage
Impact of HVC in other positions (1 and 3) Impact of the HAQ arrangement
Operation in optional room module configurations
If targets for indoor climate condition are not met,
change the length and/or
beam properties, or even
the beam type
Halton HIT Design Performance view (2D).
Halton HIT Design Performance view (3D).
4.0 m
v3
CCE/A-3800-3500+AQ(0.0)2006.03
Room: Room C
Room size: 4.2 x 4.0 x 3.0 m
Room air: 24.0 C / 50 %
Heat gain: 0 W
Instal lation height: 2 .9 0 m
Inlet water temperature: 15.0 C
Outlet water temperature: 20.1 C
Wat er mas sf low: 0 .0 40 kg /s (2 x 0 .0 20 kg /s )
Coil capacity: 858 W (2 x 429 W)
Wat er p re ssur e d ro p: 0 .6 kPa
To ta l sup ply a ir fl ow : 3 6 l/ s ( 2 x 1 8 l/ s)
Supply air temperature: 18.0 C
Prima ry ai r cap ac it y: 2 58 W ( 2 x 12 9 W)
Tot al pr es sure dro p: 8 3 P a
Total sound pressure level: 19 LpAre 10m2sab
To ta l coo ling po we r: 1 11 6 W ( 2 x 5 58 W)
Dew point temperature: 12.9 C
HVC position side=1, middle=3
Temperature d if ference: Tv3=1.2 C
Ld: -
vmax in occupied zone: v3=0.15 m/s v3(dt=0)=0.10 m/s
vlim = 0.20 m/s
Heat sources and their location may influence to the velocity and direction of the jet.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
27/4427
Management of room conditions
3.11. Management of room conditions
Air flow measurement can be implemented accurately by measuring the chamber pressure of the chilled beam.
Adjustment and balancing methods
Traditional
Proper operation conditions for chilled beams are
ensured by adjustment of airflow and water flow
rates.
Airflow rates can be adjusted by balancing the
ductwork by means of zone balancing dampers and
the balancing damper of each chilled beam. The
balancing damper can be integrated into the chilled
beam or into the connecting branch. K factors and
safety distances are presented in the HIT Design
software package.
Airflow measurement can be implemented accurately
by measuring the chamber pressure of the chilled
beam. Also, system-powered self-balancing dampers
can be used. A self-balancing damper increases the
total pressure drop to 0.16 0.6 inWC.
Water flow rates can be adjusted via zone balancing
valves and the balancing valve of each chilled beam.
Halton Adaptable
In constant-pressure zones, the unitary airflow rate
adjustment does not affect the airflow rates of other
chilled beams. Commissioning can be implemented
very effectively. Furthermore, balancing is not needed
when unitary airflow rates are adjusted, e.g., for office
room space changes.
Even constant airflow rates of office rooms can be
integrated into the same ductwork as variable air flow
rate control for meeting rooms.
Water flow rates can be controlled using an automatic
flow limiter and combined control valve for each chilled
beam, enabling individual changes in water flow rates
without the need for balancing.
Additionally, in large systems, differential pressure
valves in the pipework zones may be needed to
ensure appropriate pressure conditions.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
28/4428
Management of room conditions
Shut-off valve
Balancing valve
Control and balancing valve
Control valve with max flow limiter
Pressure regulator valve
Pressure control damper Duct balancing damper
Adaptable air balancing and adjustment with constant duct
pressure.
Traditional balancing of ductwork.
Adaptable control and maximum flow limiting valves. Traditional control and balancing valves.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
29/4429
Management of room conditions
Room control sequences
Room thermal conditions typically are controlled by
adjusting hot and chilled water flow rates in each
chilled beam by means of two-way valves.
Control can be based on on/off, pulse-width-modulated
(PWM), proportional, or proportional integral control.
Demand-based control is based on remotely set setpoints determined by, e.g., schedulers, and settings
can be adjusted locally by users according to their
demands or by occupancy mode as detected by
occupancy sensors.
In meeting and team rooms, traditional temperature
control can be complemented with an additional
sequence for increasing outdoor airflow rate (Halton
Air Quality control). This function responds rapidly to
varying ventilation requirements.
Proper heating operation can be ensured by using a
combination of room and supply air temperature
control in order to optimize the supplied air
temperature to avoid an excessive vertical room
temperature gradient.
Condensation prevention can be arranged in two
stages:
System flow water temperature control based on
room air dew point calculation for critical locations. Locally in the room, using condensate detection to
close the chilled water valve.
Control sequence for heating and cooling.
Control sequence for heating, air quality (HAQ), and cooling.
Room control applications
Room control can be realized on the basis of
functional requirements and the desired flexibility level
using:
A self-powered standalone controller
An electric standalone controller
A traditional communicative controller
A temperature sensor, typically located in the
wall-mounted user panel
The control valve and actuator types are selected to
match the required water flow rates and control
sequences. The power supply (24 / 230 VAC) for
controller, actuators, and sensors is supplied on the
basis of the units selected.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
30/4430
Case study
WP1
WP2
HVC 3 HVC 1
10 %
20 %
WP2
WP1
3.12 Case study: occupant comfort using chilled beams
The International Centre for Indoor Environment and Energy of the Technical University of Denmark (DTU) has carried out
a study measuring occupant comfort in an office environment where cooling and ventilation were provided by a ABC
chilled beam equipped with Halton Velocity Control (HVC).
Case 1
Chilled beams are installed perpendicularly to the external
wall. Velocity conditions are presented with a cooling
capacity of 16 Btuh/ft2in two different cases: Halton Velocity
Control in positions 3 and 1. Room air velocities were lower
when induction through beams was lower, even though the
cooling capacity was the same. The primary airflow rate was
the same in both cases, and compensating cooling capacity
was provided by increasing the water flow rate.
Case 2
Human responses were studied with chilled beams installed
parallel to the external wall and two persons occupying the
room. The number of people sensing a draught was clearly
(by about 60%) reduced during the maximum cooling
capacity period with HVC in the throttle position (1). While
the person near the window surface (WP2) felt slightly
warmer (PMV increased from 0.4 to 0.7) when HVC was
used, the acceptability increased slightly.
Case 1. Air velocities (fpm) in the occupied zone with Halton Velocity
Control in full position.
Thermal conditions (temperature and velocity) in theoccupied zone were measured in this study, along
with human responses, using both thermal manikins
and living people. The following conclusions were
drawn after analysis of the measurement results:
High quality of general thermal comfort can be
achieved.
Halton Velocity Control decreases velocities and the
potential risk of draught discomfort.
Increased heat load and supply flow rate togetherincrease the risk of local discomfort.
Airflow interaction is an important factor affecting
thermal comfort.
The layout of chilled beams and workplaces should
be carefully considered.
Thermal flows from warm or cold windows are
important factors in air distribution and occupants
local thermal comfort.
Case 1. Air velocities (m/s) in the occupied zone with Halton Velocity
Control on in throttle position.
Case 2 : Percentage of people sensing a draught (22 Btuh/ft2).
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
31/4431
Passive chilled beam system
4.1. Passive chilled beam system
Chilled beam system description
Haltons chilled beam system is an air conditioning
system for cooling applications where good indoor
climate and individual space control are appreciated.
The passive chilled beam system utilises the excellent
heat transfer properties of water and provides a good
indoor climate energy-efficiently.
Operation of the system
Chilled beam systems are designed to use the dry
cooling principle, operating in conditions in which
condensation is prevented by control applications.
Ventilation
Ventilation in passive chilled beam systems typically is
arranged using mixing ventilation with ceiling or wall
diffusers. Alternatively, floor diffusers can be used.
In passive-service chilled beams, a diffuser can be
integrated into the beam unit for air supply.
Cooling
Chilled water circulates through the heat exchanger of
the passive chilled beam unit, resulting in relatively
high cooling capacities.
Passive beam operation is based on free convection in
the heat exchanger. Passive chilled beam units with a
higher proportion of radiation also exist.
Heating
Heating generally is realised with a separate heating
system.
A separate heating system e.g., perimeter heating
typically is used in passive chilled beam
installations.
Window draughts due to radiation and downward
convective air movement during cold seasons need
to be eliminated.
Schematic diagram of a chilled beam system office floor installation.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
32/4432
4.2 Chilled beam system design
A passive chilled beam system can be designed to fulfil requirements for sustainable, energy-efficient buildings that
provide flexible use of space and a healthy and productive indoor climate. A passive chilled beam system can realise
excellent indoor climate conditions in terms of thermal and acoustic properties in a wide range of installation
scenarios.
TYPICAL INPUT VALUES AND OPERATION RANGES
Room temperature, summer 73 77 F
Room temperature, winter 68 72 F
Water inlet temperature, cooling 57 61 F
Target water flow rate 0.4 1.6 gpm
Sound level NC 30
Cooling capacity / floor area 25 Btuh/ft2 38 Btuh/ft2 *
Cooling capacity / effective unit length 250 Btuh/ft 400 Btuh/ft *
Separately for ventilation
Supply air temperature 61 66 F
Outdoor air flow rate/ floor area,
offices 0.33 0.55 cfm/ft2
meeting rooms 0.33 0.9 cfm/ft2
Note * It is reasonable to study the room air velocity
conditions carefully
Note ** It is reasonable to study the thermalconditions carefully
Ventilation and air diffusion arrangement
The supply airflow rate shall be high enough to
remove internal humidity loads.
Cooling using chilled beams
Required cooling capacities should be no more than
19 25 Btuh/ft2. With well-dimensioned integrated
applications, capacities as great as 38 Btuh/ft2can
be realised.
Thermal properties of the external walls and window
construction should be reasonable.
Airtight windows with effective solar shading are
used.
The cooling capacity of passive chilled beams is
typically 150 250 Btuh/ft to avoid draughts in the
occupied zone, especially underneath the unit.
Operation shall be designed with conditions in the
occupied zone in all seasons (winter, summer, and
intermediate season) taken into account.
The flow water temperature (typically above 57F)
must be sufficiently high to avoid condensation in all
operation conditions. If necessary, the inlet water
temperature may be adjusted to compensate for
outdoor or indoor conditions. A condensation sensor
should be located in each zone.
Water flow rates and pressure drops in chilled
beams should be in line with chilled water pipework
design and pumping cost target levels.
Passive chilled beams installed in a suspended
ceiling always require sufficiently large openings in
the ceiling for the induced room air path.
Location of chilled beams shall respect the minimum
distances from walls and ceiling presented in the
section Passive chilled beam orientation and
ventilation arrangements.
Passive chilled beam system design
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
33/4433
The appropriate model of passive chilled beam unit is selected
by taking into account the following factors:
Architectural design
Preferred appearance
Exposed installation or flush mounting in suspended ceiling
Hidden installation above perforated/grid ceiling
Adaptation to ceiling
Positioning in consideration of light fittings Integration of light fittings
Unit dimensions
Room design grid dimensions
Requirements for flexibility and eventual partition wall locations
Supply air diffuser integration
Exhaust valve integration
Cooling capacity requirements
A passive beam can be integrated into a suspended ceiling via a
ceiling plenum, allowing closed return air circulation.
Building services can be integrated into chilled beams, creating
an elegant and uniform ceiling appearance. Multi-service passive
beams are a cost-effective and interesting concept especially for
renovation projects where there is a desire to maximise ceiling
height or existing ceiling appearance should be largely
preserved.
Common technical services for integration are:
Light fittings, controls, sensors, detectors, and cabling
4.3. Passive chilled beam model selection
Passive beams in ceiling void
Customised customized service beam.
Closed passive chilled beam integrated into
suspended ceiling.
Passive chilled beam in exposed installation.
Passive chilled beam in ceiling-void-mounted
installation.
Passive chilled beam model selection
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
34/44
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
35/4435
4.4. Passive chilled beam orientation and ventilation arrangements
Passive chilled beams can be installed either perpendicularly or parallel to the perimeter wall. The units should not
be positioned directly facing work spaces, to ensure comfortable velocity conditions. Minimum recommended
installation distances from walls and between parallel chilled beams shall be respected, for proper cooling
performance.
Side wall installation & ceiling diffuser.
Ceiling diffuser between chilled beams.
Selection of passive chilled beam orientation Indoor climate conditions
Capacity per chilled beam unit
Residual velocities for the occupied zone
Convective plume interaction with supply air jet
Suitability for room module dimensions
Suitability for the lighting fixture locations
Flexibility for layout changes
Minimum distance between parallel beams
Minimum distance between chilled beam and wall/
ceiling
Perimeter installation & ceiling diffuser.
Side wall installation & wall diffuser.
Side wall installation & floor diffuser. Side wall installation & low-velocity unit.
Passive chilled beam orientation and ventilation arrangements
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
36/4436
Passive chilled beam location
Chilled beam units shall be installed respecting
minimum recommended distances from walls and
ceiling in order to ensure effective convection and
proper operating conditions:
H1 = min. 0.25 x W when S > W
H2 = min. 0.5 x W when S < W
Minimum distance between chilled beam units of L, to
ensure effective operation:
L = min. 3 x W
When a passive chilled beam is installed above a
perforated or grid ceiling, the following minimum
distances should be respected:
H3 = min. 1 in
The open area percentage (OAP) of the suspended
ceiling shall be sufficiently high to ensure proper
functioning of the chilled beam.
The minimum percentage of open area for perforation
is 25%. The minimum hole diameter is 1/8 in.
Side panel extensions can be used to improve
buoyancy effect and thus cooling capacity.
Use HIT Design for calculation of cooling capacity,
taking installation above the perforated ceiling with or
without side panel extensions into account.
Exhaust air unit location
In cases where chilled beams are installed above a
suspended ceiling, exhaust units should not be
installed above the suspended ceiling.
Otherwise, exhaust unit position is of minor
importance in the installation.
Minimum distances for passive chilled beam installation.
Passive chilled beam installed above a perforated or grid ceiling.
Passive chilled beam orientation and ventilation arrangements
Hsk, Correction factor, in
4 1.19
6 1.28
12 1.40
16 1.45
Side panel extension effect on cooling capacity.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
37/4437
Operation range definition
4.5. Operation range definition
Chilled beam operation range is defined on the basis of representative rooms. The selected rooms are studied to
determine cooling and heating loads. After specification of load patterns in the representative rooms, chilled beam
operation parameters are set. The design target values can be verified via a full-scale mock-up or computational fluid
dynamics (CFD) simulation.
Typical input values and operation ranges (extreme target values in brackets)
Room temperature for cooling 73 77 F
Water inlet temperature for cooling 57 61 F
Target water flow rate for cooling 0.32 1.6 gpm
Cooling capacity per unit floor area 25 (38) Btuh/ft2
Cooling capacity / effective beam length 250 (400) Btuh/ft
Comfort / PMV -0.5 ... +0.5
Draught rate (DR) < 15%
Local mean room air velocity Cooling: 45 fpm
Heating: 35 fpm
Definition of design conditions and operation
parameters
Cooling capacity demand in spaces, in Btuh/ft2, and
actual breakdown of loads
Heating capacity demand in spaces, in Btuh/ft2, and
actual breakdown of loads
Ventilation arrangement
Diffuser type, size, and number Ventilation rates in spaces as rate per floor area, in
cfm/ft2
Ventilation rate in spaces as rate per person, in cfm/
person
Model rooms and operational parameters
Room temperature
Supply air temperature
Water inlet temperature
Target duct pressure level
Target water flow rate Maximum sound pressure level
Verification of target design values with full-scale mock-up and CFD
simulation.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
38/4438
Pre-selection and selection
Pre-selection
With the help of quick-selection tables, pre-select the
chilled beam using the following parameters for the
desired design conditions:
Indoor climate conditions
Cooling capacity
Minimum distance between parallel units
4.6. Pre-selection and selection
Make your design process more efficient. Haltons design tools for the pre-selection and selection phase include
brochure data sheets with quick-selection charts and the Halton HIT Design software. Halton HIT Design enables
product selection and performance simulation for the product(s) that addresses, e.g., air velocity, cooling and
heating capacity, throw pattern, sound level, and location of the units.
APA cooling capacity, in Btuh/ft of
effective length
Water flow rate:
1.27 gpm
Difference between room air and water mean temperatures,
degF
Coil height (in) Coil width (in) 11 13 14 15 16 17 18 20
3 12.4 91 116 132 147 163 176 190 232
3 18.3 143 182 211 234 253 279 301 335
3 24.2 190 241 283 303 322 362 401 465
4 12.4 108 135 155 170 186 203 217 253
4 18.3 177 220 258 284 310 335 358 4184 24.2 225 280 330 364 395 426 457 532
Pre-selection example
Room dimensions 8 x 13 x 9
Room area 104 ft2
Room temperature 75 F
Ventilation rate 42 cfm
Supply air temperature 64F
Required total cooling capacity 22 Btuh/ft2
Cooling capacity 2700 Btuh
Cooling by ventilation 491 Btuh
Coil cooling capacity 1931 Btuh Presumed temperature difference DT = 14 degF
Select APA-4-153--1 159 Btuh/ft
Chilled beam APA cooling capacity, in watts per metre of effective length for water flow rate 1.27 gpm
CPA passive chilled beam quick-selection
Cooling capacity over unit length (W/m) presented for
water flow rate qmw
= 1.27 gpm.
Estimate the temperature rise in the chilled beam
(typically 2 5 degF), and calculate the temperature
difference between room air and water mean
temperature.
Temperature difference Tr- (T
w1+ T
w2)/2, degF
Where
Tr Room temperature, F
Tw1
Water flow temperature, F
Tw2
Water return temperature, F
Check the temperature difference with the HIT Design
software.
Water flow rate
qmw, gpm 0.024 0.32 0.40 0.48 0.55 0.63 0.71 0.79 0.87 0.95 1.27
0.79 0.83 0.86 0.88 0.91 0.92 0.94 0.96 0.97 0.98 1
Correction factor of cooling capacities for water flow rates deviating from 1.27 gpm flow rate.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
39/4439
Pre-selection and selection
1. Design data in cooling
Specify the temperature difference between the
inlet and outlet water of the beam or, optionally,
insert the inlet water temperature and target water
flow rate.
Calculate the coil capacity using HIT Design, and
compare the coil capacity against the requirement.
You can also insert the supply air flow rate and
temperature for total cooling capacity calculation.
2. Chilled beam location and velocity control
adjustment
The location and number of chilled beams are
specified (also, asymmetric positioning is possible).
You can also add a person for evaluating the air
velocity locally
directly below the chilled beam
in the vicinity of the beam at floor level
further from the chilled beam at floor level
3. Space results / unit performance
Check operation parameters against system
operation conditions to verify that the operation
parameters respond to those of the system, as in
the cooling case.
Selection
Calculate the cooling and heating capacity of the selected chilled beam units by studying chilled beam performance
in selected model rooms with desired operation parameters, using Halton HIT Design.
Design Data window in Halton HIT Design selection.
Room dimensions, the occupied zone, and design criteria are
specified in the Room window in Halton HIT Design.
1 2
3
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
40/4440
Indoor climate conditions
If indoor climate conditions targets are not met,
then change
the beam length or number of beams and/or
beam properties or even
beam type and
diffuser type and/or location
Study optional room modules
Water flow rate (keep at the same level as before)
Operation at optional room cooling load levels / room
usage
4.7. Design of indoor climate conditions
Simultaneously with the performance values, verify also that the predicted room conditions are acceptable,
particularly the air velocities entering the occupied zone created by the convective plume of the chilled beam. Take
into consideration the interaction of the passive beam and the supply air distribution as well.
Operation in optional room module configurations
Study the velocities of the convective plume
entering the occupied zones and room air
velocities
Plume velocities entering the occupied zones (in the
design case)
Room air velocities in the occupied zone
Temperature difference between the plume and
ambient room air
Check the interaction of the falling convective
plume of a chilled beam and supply air throw
pattern
Simultaneously with the performance values, verify
that the predicted room conditions are acceptable,
providing efficient air distribution.
Supply jet adequately reaching the occupied zone
level Supply air that is not directed directly to chilled
beam air circulation
Halton HIT Design Performance view (2D).
Stationary person below and to the side of a chilled beam.
Interaction of convective plumes of a chilled beam
and a stationary person
Note that the rising convective plume of a stationary
Stationary person located directly below a chilled beam.
person affects the flow pattern of a chilled beam and
that the prevailing velocities above the person are
lower than in undisturbed flow created by a chilled
beam.
2.5 m
vop
CPA-100-3900-315-1Cooling 2007.05
Room:
Room size: 2.5 x4.0 x2.8 m
O ccu pi ed z on e: h =1 .8 m / dw =0 .5 m
Room air: 24.0 C / 50 %
Heat gain: 700 W
P erf or at ed ce il in g: -
I ns ta ll at io n he ig ht : 2 .7 0 m
Inlet water temperature: 15.0 C
Outlet watertemperature: 16.7 C
Wa te r fl ow r at e: 0 .0 80 kg /s
Coil capacity: 575 W
155 W/m
W at er p r es su re d r op : 5 . 6 k P a
S up pl ya ir fl ow r at e 2 0 l /s
2.0 l/(sm2)
Supply ai r t emperature: 18.0 C
J et outl et t emperature: 21.4 C
P ri ma ry a ir c a pa ci ty : 1 4 3 W
To ta l pr es su re d ro p: -
Totalsoundpressurelevel: -
T ot al c o ol in g c ap ac it y: 7 1 8 W
72 W/m2
Dewpoint t emperature: 12.9C
Velocity control: -
Velocity point
v
T
vop
~0.15m/s
vlim= 0.20m/s
2.5 m
v3
vop
CPA-100-3900-315-1Cooling 2007.05
Room:
Room size: 2.5 x4.0 x2.8 m
O ccu pi ed z on e: h =1 .8 m / dw =0 .5 m
Room air: 24.0 C / 50 %
Heat gain: 700 W
P erf or at ed ce il in g: -
I ns ta ll at io n he ig ht : 2 .7 0 m
Inlet water temperature: 15.0 C
Outlet watertemperature: 16.7 C
Wa te r fl ow r at e: 0 .0 80 kg /s
Coil capacity: 575 W
155 W/m
W at er p r es su re d r op : 5 . 6 k P a
S up pl ya ir fl ow r at e 2 0 l /s
2.0 l/(sm2)
Supply ai r t emperature: 18.0 C
J et outl et t emperature: 21.4 C
P ri ma ry a ir c a pa ci ty : 1 4 3 W
To ta l pr es su re d ro p: -
Totalsoundpressurelevel: -
T ot al c o ol in g c ap ac it y: 7 1 8 W
72 W/m2
Dewpoint t emperature: 12.9C
Velocity control: -
Velocity point
v
T
v3
~0.25m/s
-2.6C
vop
~0.15m/s
vlim= 0.20m/s
2.5 m
v3
vop
CPA-100-3900-315-1Cooling 2007.05
Room:
Room size: 2.5 x4.0 x2.8 m
O cc up ie d zo ne : h =1 .8 m / dw= 0.5 m
Room air: 24.0 C / 50 %
Heat gain: 700 W
P er fo ra te d ce il in g: -
I ns ta ll at io n he ig ht : 2 .7 0 m
Inlet water temperature: 15.0 C
Outlet watertemperature: 16.7 C
Wa te r fl ow ra te : 0 .0 80 k g/ s
Coil capacity: 575 W
155 W/m
W at er p r es su re d r op : 5 .6 k Pa
S up pl y a ir f lo w ra te 2 0 l /s
2.0 l/(sm2)
Supply ai r t emperature: 18.0 C
J et outl et t emperature: 21.4 C
P ri ma ry a ir c a pa ci ty : 1 4 3 W
To ta l pr es su re d ro p: -
Totalsoundpressurelevel: -
T ot al c o ol in g c ap ac it y: 7 1 8 W
72 W/m2
Dewpoint t emperature: 12.9C
Velocity con trol: -
Velocity point
v
T
v3
~0.25m/s
-2.6C
vop
~0.05m/s
vlim= 0.20m/s
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
41/4441
Adjustment and balancing methods
Proper operation conditions for chilled beams are
ensured by correct water flow rates.
Water flow rates can be adjusted via zone balancing
valves and the balancing valve of each chilled beam.
Water flow rates can also be controlled using an
automatic flow limiter and combined control valve foreach chilled beam, enabling individual changes in
water flow rates without the need for balancing.
Additionally, in large systems, differential pressure
valves in the pipework zones may be needed to
ensure proper pressure conditions.
4.8. Management of room conditions
Water flow measurements can be implemented by measuring pressure drop over a balancing valve equipped with
measurement taps.
Room control
Room thermal conditions typically are controlled by
adjusting hot and chilled water flow rates in each
chilled beam by means of two-way valves.
Control can be based on on/off, pulse-width-modulated
(PWM), proportional, or proportional integral control.
Demand-based control is based on remotely setsetpoints determined by, e.g., schedulers, and settings
can be adjusted locally by users according to their
demands or by occupancy mode as detected by
occupancy sensors.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
42/4442
Customised service beams
5. Customized service beams
Traditional chilled beam installations include ventilation, cooling, and heating next to the equipment for other ceiling-
based services. The customised service beam concept proposes an all-in-one solution for all ceiling-mounted
accessories. The service beam concept is suitable for both suspended-ceiling and exposed installations. The
product's appearance can be tailored to suit the interior.
The concept offers benefits from the time of installation through a whole lifetime of use:
An improved indoor climate is a result of excellent
temperature conditions and silent, draught-free
operation. Good conditions promote productivity and
the health of users.
Flexibility for different layouts, from open-plan to
partitioned office space, is achieved efficiently.
Assembly at the factory increases installation speed
and quality while reducing costs. Rapid connections
further reduce the commissioning time on-site.
Having a single source of responsibility lowers risk
and reduces the need for co-ordination.
Luminaires can be integrated into chilled beams or
installed as separate light fittings, regardless of chilled
beam orientation. Chilled beams are available with
direct and/or indirect luminaires.
With fewer separate pieces of equipment fixed to
the ceiling and walls, interior design better matches
the architectural vision.
The investment cost is more competitive than that of
traditional systems and suspended-ceiling
installations with separate building services.
Competitive running costs are achieved with low
maintenance demands and energy consumption.
Room height is increased, as no suspended ceiling
is needed.
Luminaires
Direct and indirect luminaires integrated into the
bottom plate of the beam provide good contrast and
visual comfort. Direct and indirect lighting can be
implemented with separate light fittings or with one
fitting for both. All lights can be equipped with built-in
on/off or dimmable control and different connection
options.
Also, emergency lights can be integrated into the
chilled beams.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
43/4443
Customised service beams
Detectors
Occupancy sensors allowing for demand-based
ventilation and other occupancy-related features, as
well as daylight sensors and smoke detectors, can be
integrated into the chilled beam.
Controls
Chilled beam delivery can include integrated two-way
control valves with actuators and condensation
sensors. When necessary, the beam structure can also
include a room controller and the associated
temperature sensor
Space for sprinklers
National building codes typically require sprinkler
installations to be carried out on the site.
However, the sprinkler pipes can be attached above
the beams and the pipe connections for individual
sprinkler nozzles, to an accessory space in the middle
of the beam.
Public address loudspeakers
Public announcements or background music can be
provided through built-in pre-wired speakers.
Cable shelves
Cables for various services can be laid on cable
shelves, which can be integrated in the chilled beam
design in order to complete the elegant installation.
-
8/13/2019 Halton HVAC Handbook Chilled Bean Design Guide
44/44
www.haltoncompany.com