1. Chris Lawrence
VP Sales & Marketing

2. AGENDA Chilled Ceilings & Beams ? Part 1 – Passive Systems
So what are
Chilled Ceilings & Beams ?
Part 1 – Passive Systems
Chilled Ceilings
Chilled Sails
Passive Beams
Part 2 – Active systems
Active Chilled Beams
Part 3 - Reducing Energy
Space Humidity concerns
Design Considerations
Water System Design
Savings & LEED
Part 4 - Solutions
All Air Core
6 Way
LoFlo
Overall 1st Costs

3. So What are Chilled Ceilings & Beams?
A sensible cooling only device that uses chilled water above the room dew point to remove heat from the space.
They can be independent of, or combined with, a method of introducing conditioned outside air to the space to meet the ASHRAE 62 ventilation requirements

4. Radiant & Convective sensible cooling independent of
Chilled
Ceilings
Radiant & Convective sensible cooling independent of
Primary air delivery

7. Chilled Ceiling Radiant Effect
76°F Dry Bulb
74°F radiant
temperature (black bulb)

8. Chilled Ceilings Advantages Design Issues Excellent thermal comfort
Can Heat
Reduced space requirements
Will fit into 6-8” cavity
Self regulating
Simple controls
Low noise
Low maintenance
Low cooling output
20 to 25 BTUH/FT2 100% coverage
14 to 18 BTUH/FT2 70% coverage
Driven by surface area
Very High cost
Separate air system required
Needs many connections

10. Sensible cooling independent of
Sails
Sensible cooling independent of
Primary air delivery.

11. Sails Operation Principle

12. Sails Operation Principle
Increased convection

13. Chilled Sails Advantages Design Issues Good thermal comfort
Reduced space requirements
Freely suspended
Self regulating
Simple controls
Low noise
Low maintenance
Cooling output
40 to 50 BTUH/FT2
dependent of amount of ceiling used
Separate air system required
High cost
Can not heat
Need good acoustic treatment to avoid hard spaces
Many connections
Aesthetics ?

15. Ceilings & Sails Summary -
Cooling & Heating (Ceiling only)
Very High thermal comfort especially on ceilings
Cooling capacity up to 18 Btuh/FT2 floor space (Ceiling - average)
Cooling capacity up to 40 Btuh/FT2 floor space (Sail - average)
Very low ceiling cavities needed, could in installed in a 6” space.
Self regulating
simple two position controls
Low noise
Low maintenance

16. Buoyancy driven sensible cooling independent of
Passive
Beams
Buoyancy driven sensible cooling independent of
Primary air delivery

17. Passive Chilled Beams Operation Principle
Perforated tile
Water coil
Suspension rod
Soffit
Fabric skirt

18. Passive Chilled Beams Airflow Pattern

19. Façade driven cooling

20. Above the ceiling recessed

21. Exposed

22. Passive beams Advantages Design Issues Good thermal comfort
Low terminal velocities
Self regulating
Simple controls
Low noise
Low maintenance
Ideal ‘top up’ to UFAD especially at the façade
Cooling output
40 to 50 BTUH/FT2
Separate air system required
Need High free area ceilings
Can not heat
Need deep ceiling cavity and space above coil
Need separate return air passage for remove primary air volume

23. Typical Installation

24. Passive Beams Summary -
Cooling only
Good thermal comfort
Cooling capacity up to 50 Btuh/FT2 floor space
Up to 450 BTUH per LF of beam
Reduced ductwork, riser and plant sizes
Water transports most of sensible cooling
Self regulating
simple two position controls
Low noise
Low maintenance

25. Passive beams – Perforation beware!
Perforation Free Areas
Are critical to passive beam performance !
Painted ?
Usually, perforated free areas are quoted prior to paint application !
On a recent project
The tiles were specified 28% free area 1/10” hole. These turned out to be when painted a 1/12” hole which equated to
19% free area.
This reduced the reduced performance by a further 20%
Rule of Thumb
Minimum 1/8” hole, approx 45% free area preferred, any reduction in hole size or free area reduces output therefore it costs you more because you need more beams

26. Passive beams – Return air passage
Passive beams need a return air passage to feed the coil, typically the same area as the coil, split along the 2 long sides of the beam.
As important, the removal of the fresh or conditioned air must have a
Separate return route if the return is via the celling cavity/void. Better to have a ducted return!

27. AGENDA Active Chilled Beams Part 2 – Active systems
Part 3 - Reducing Energy
Space Humidity concerns
Design Considerations
Water System Design
Savings & LEED
Part 4 - Solutions
All Air Core
6 Way
LoFlo
Overall 1st Costs

28. So What are Chilled Ceilings & Beams?
A sensible cooling only device that uses chilled water above the room dew point to remove heat from the space.
They can be independent of, or combined with, a method of introducing conditioned outside air to the space to meet the ASHRAE 62 ventilation requirements

29. Chris Lawrence
VP Sales & Marketing

30. Sensible cooling combined with primary air delivery
Active
Beams
Sensible cooling combined with primary air delivery

31. Active Chilled Beam Operation Principle - Horizontal coil
Primary air nozzles
Primary air plenum
Suspended ceiling
Heat exchanger

32. Active Chilled Beam Operation Principle - Vertical coils
Primary
air supply
Slab
Suspended Ceiling

33. Velocity Streamlines

34. Active Chilled Beam Airflow Pattern 2-way

35. Active Chilled Beams 2 way

36. Active Chilled Beams Exposed -2 way

37. Active Chilled Beams Perimeter - 1 way

38. Active Chilled Beams 1 Way perimeter (Concealed)

39. Thermal Comfort Perimeter CFD
Good air movement throughout the room with ≈ 3-4:1 entrainment ratios
Uniform temperatures and no drafts by thorough mixing of the primary and room air

40. Active Chilled Beams 1 Way perimeter (Concealed)

41. Active beams Advantages Design Issues
All services in celling, integrated cooling, ventilation and heating
Lower pressure than traditional induction systems
Self regulating
Simple controls
Low maintenance
Fiber tile ceilings
Lower ceiling cavity, lower slab to slab
Cooling output
to 100 Btuh/FT2 , beam outputs up to 1800 Btuh/LF
Can be 2 or 4 pipe
Can heat
Need more primary air than minimal fresh are, suggest .3 cfm/SF
Primary air controls dew point

42. Rule # 1
The Design with the fewest number of chilled beams will be the lowest 1st cost install, therefore performance matters.

43. Performance matters

44. Reducing energy

45. Heat Removal Active Chilled Beam concept
Airflow requirement
reduced by 70%
70% of sensible heat removed by chilled beam water coil
30% of sensible heat removed by air

46. Chilled Water
On a Mass Flow Rate Basis:-
1 lbs of chilled water (6°Δt) transports 4x more cooling energy than 1 lbs of air (20°Δt)
As water weighs 800 times that of air
On a Volume Flow Rate Basis:-
1 FT³ of chilled water transports 1000 more cooling energy than 1 FT³ of air (20 Δt)
Transportation Energy
Transportation of a ton of cooling by air requires 7 to 10 times more energy than by chilled water.

47. U.S. Energy Consumption
Courtesy of USGBC

48. U.S. Energy Consumption
Courtesy of USGBC

49. Fan Energy Use in Buildings
“Energy Consumption Characteristics of Commercial Building HVAC Systems” - publication prepared for U.S. Department of Energy

50. Heat Removal Ratio Airflow requirement reduced by 70%
70% of sensible heat removed by chilled beam water coil

51. Rule # 2
If your not reducing the air volume in a space by 25%, you could be installing a very expensive diffuser

52. Rule # 3
Even if your using chilled beams on your design, you don’t have to use them everywhere.

53. Water = Efficient Transport
10”
1 Ton of Cooling
requires 550 CFM of air or
4 GPM of water
10”
¾” diameter
water pipe

54. ‘Water’ is a better cooling medium, than air !
‘Water’ takes less
energy to transport
than air !

55. So a room ‘BTU/h is still a BTU/h’, however
Room Load is still Room load
Chilled Ceilings & Beams do not lower the heat load of a space, solar gain is still a gain, lights and equipment still give off heat and so do people.
So a room ‘BTU/h is still a BTU/h’, however .

56. Only enough
‘chilled Water’ is
Chilled to 45°F
to dehumidify the reduced
primary airflow requirement.
So less energy is used to
produce the beams ‘chilled water’
at 58°F - saving energy

57. We need less
primary air,
making
100% DOAS ideal and cost effective, Improving IAQ
& Ventilation effectiveness

58. Space Humidity Concerns

59. REHVA (Federation European Heating & Ventilation) Publication
Independent Publications
This years 2012 ASHRAE HVAC Systems and Equipment publication covers chilled beam basics
REHVA (Federation European Heating & Ventilation) Publication
AHRI Test Standard (being worked on)
Part of the European Commission ‘Energie’ program, in partnership with COSTIC (France), BSRIA (UK), ISSO (Netherlands) & IDEA (Spain).
Climatic Ceilings - Technical Note: Design Calculations
Climatic Ceilings and Chilled beams - Application of low temperature heating and high temperature cooling

60. Relative to room air dew point
Extract From Independent ‘Energie’ Climatic Ceilings
Passive
+ 0.5 °C ( °F )
Active
- 1.5 °C ( °F)
Relative to room air dew point

61. 64˚ Dew Point
75˚/70% RH
58˚ CWS
75˚/50% RH
55.1˚ Dew Point

62. Condensation Considerations
75ºF db room design temperature at 50% relative humidity 55.1ºF dew point temperature
Theoretically condensation will form on the coil when the chilled water temperature is 55ºF.
Apparent room dew point is 2-3ºF lower due to insulating effect of a water film on coil fins
In reality at this room design condition, condensation in the form of droplets will not begin to form until the water temperature is 52-53ºF.

63. Condensation Consideration
Condensation after 8.5 hours on a chilled surface intentionally held 7.8F colder than the space DPT. Not one droplet fell under these conditions
Chilled Ceilings in Parallel with Dedicated Outdoor Air Systems: Addressing the Concerns of Condensation, Capacity, and Cost Stanley A. Mumma, Ph.D., P.E.

64. ‘Active Chilled beams could be run at or below the room dew point, but that’s crazy’!
Be safe, design at 2 to 3F above the dew point and control the moisture content of the primary air to control the room RH 64

65. Rule # 4
If you can not measure and control the space humidity, and your not in the middle of the desert, don’t use chilled beams !

66. Design Considerations

67. Building Suitability
Building Characteristics that favor Active Chilled Beams
Zones with moderate-high sensible load densities
Where primary airflows would be significantly higher than needed for ventilation
Buildings most affected by space constraints
Hi – rises, existing buildings with induction systems
Zones where the acoustical environment is a key design criterion
Laboratories where sensible loads are driving airflows as opposed to air change rates
Buildings seeking LEED or Green Globes certification

68. Building Suitability
Characteristics that less favor Active Chilled Beams
Buildings with operable windows or “leaky” construction
Beams with drain pans could be considered
Zones with relatively low sensible load densities
Zones with relatively low sensible heat ratios and low ventilation air requirements
Zones with high filtration requirements for the re-circulated room air
Zone with high latent loads

69. Required Design Data Room Design Conditions
Room Sensible Cooling Loads
Room Latent Cooling Loads
Room Heating Loads (if used for heating)
Infiltration Loads
Minimum Outside Air Quantity per Zone
Secondary Chilled Water Conditions and Flow
Primary Air Conditions and Inlet Pressure
Desired Room Air Change Rate (if required)
Spatial Considerations/Constraints
Room layout/Drawings
Unit models desired

70. Role of the Primary Air Ventilate the occupants according to ASHRAE 62
Handle all of the latent load in the space
Primary air is only source of latent heat removal
Create induction through chilled beam
Pressurize the building

71. Primary Air Design Central AHU sized to handle: AND
sensible and latent cooling/heating of the ventilation air
portion of the sensible internal cooling/heating loads
AND
all of the internal and infiltration latent loads
Primary air delivered continuously to the chilled beams
VAV primary air can be considered for the perimeter if the sensible loads are high
Chilled beam water coils provide additional sensible cooling/heating to control zones

72. Water System design

73. CHW System Design Options
Secondary loop
Tap into district CHW loop
Heat exchanger into return – no GPM demand
Can increase main plant efficiency
Dedicated chiller & DX
Dehumidification by DX AHU
Significantly increased COP - 11+
Twin chillers
One for AHU’s – 6 COP
One for chilled beam circuit – 11+ COP

74. Secondary Loop Supply temperature monitor
Secondary chilled water supply to beams T
Primary chilled water supply S
SCHW Pump
Heat Exchanger
Secondary chilled water return
Primary chilled water return

75. Dedicated Chiller To chilled beam zones Bypass Valve T Chilled water
pump
64°F
Cooling Tower
Geothermal Loop
Dedicated chiller
11+ COP
Geothermal Heat Pump
58°F

76. District Chilled Water Loops
Tap into return pipe with heat exchanger and secondary loop
No demand in district loop GPM
Increases main chiller plant COP

77. Waterside Economizer
With mid-high 50ºFs chilled water temperature serving the Active Chilled Beams
Reduce chiller energy consumption through:
Using a water side economizer to minimize the chiller operating hours serving the Active Chilled Beams

78. Reverse Return Pipe Design

79. Boiler Efficiency Lower Hot Water Temp
Hot water typically F
Reduce boiler energy consumption by maximizing efficiency of a condensing boiler through very low return water temperatures
Use of water to water heat pumps
(KN boiler efficiency chart courtesy of Hydrotherm)

80. Savings & LEED

81. Energy Savings Compared to VAV

82. Call Center, Kentucky Case Study
Call center, 350,000 sq ft
2200 occupants
LEED design
Considered radiant ceilings and passive beam systems
Article in ASHRAE Journal, December 2009

83. Call Center, Kentucky Case Study
Real energy results based on comparison with another building on the same campus
Energy usage data collected over 1 year
Electrical energy consumption reduced by 41%
Natural gas consumption reduced by 24%

84. First Costs Compared to VAV
“Energy Consumption Characteristics of Commercial Building HVAC Systems” - publication prepared for U.S. Department of Energy

85. Maintenance No moving parts No filter No condensate pumps
No consumable parts
Up to 4 year inspection & clean
Easy maintenance access

86. (Minimum 40 points needed for certification out of 100 maximum)
LEED Certification
Optimize Energy Performance - up to 48% (new) or 44% (existing)more efficient than ASHRAE 90.1 (EA Credit 1) - up to 19 points
Increased Ventilation - 30% more outdoor air than ASHRAE 62 (IEQ Credit 2) - 1 point
Controllability of Systems - individual temperature control (IEQ Credit 6.2) point
Thermal Comfort - meet ASHRAE 55 (IEQ Credit 7.1) point
(Minimum 40 points needed for certification out of 100 maximum)

87. Solutions to reduce cost

88. All Air Core

89. Active Chilled Beam Low Cost Core Solution
When the sensible load densities in the interior zones are relatively low, the zone sizes large and the first cost of an Active Chilled Beam system is an issue consider:
An Active Chilled Beam perimeter system in the high sensible load density perimeter zones
A single duct VAV interior system in the low sensible load density interior zones
Low supply air temperature to the single duct VAV with induction diffusers to increase the supply air temperature
This needs separate air handers for perimeter & internal/core areas

90. Interior Zones Induction Diffuser
277 cfm
48ºF
277 cfm
75ºF
555 cfm
60ºF

91. Lower airflows and fan energy consumption in the interior VAV system through use of lower temperature primary air - 20% reduction if temperature lowered from 55ºF to 50ºF - 26% reduction if temperature lowered from 55ºF to 48ºF
Improved comfort through increased air movement in the low load interior zones
Increased latent cooling capacity and improved humidity control

92. Latent 640 Btuh
Latent 1408 Btuh
2.2 times latent capacity for same sensible capacity with 26% less primary air

93. 6 Way valve

94. 6-way valve
4-pipe flexibility at 2-pipe cost

95. 2 or 4 Pipe Chilled Beams? Higher coil performance
4 pipe performance is compromised
75% Cooling (12 pipes)
25% Heating (4 pipes)
Fewer or shorter beams
Lower hot water temperatures
90°F for 2 pipe
130°F for 4 pipe

96. 2-Pipe Beams and Terminal Heating
Chilled Water Supply
Terminal Heating Coil
Hot Water Supply
2-Pipe Active Chilled Beams
Hot Water Return S T
Chilled Water Return S

97. 6-way valve

98. 6-way valve

99. 6-way valve One valve per zone
4-pipe to zone then 2-pipe to chilled beams
Half controls costs
Increased chilled beam performance
Increased energy efficiency

100. LoFlo

105. Advantages
Reduced pipework
Higher system Delta T
Reduced pumping flow and horse power
Increased flexibility
Eliminate flow control valve and balancing valves
Reduced commissioning
Multiple water temperatures
Increased capacity at chilled beam (no 4-pipe req.)
Used in conjunction with 6 way valve
LMB requires no maintenance
One LMB for each zone (multiple ACB’s)
Simple cartridge replacement

106. Disadvantages
Power required to each LMB
Requires low temperature water at thermal plant

107. Overall
1st cost

108. Viterbo School of Nursing, WI
New $15.8m facility (original estimate $20m)
68,000 ft2, 7 floors
Consists of labs, lecture halls and classrooms
LEED Silver Certification
Completion fall 2011

109. HVAC First Costs Savings Compared to VAV
Smaller AHU’s
Smaller ductwork
Controls
Simple two position zone valves
Electrical infrastructure costs
Increased pump HP more than offset by reduced fan HP

110. HVAC First Costs Increases Compared to VAV
More terminals (beams)
More distribution piping
More piping insulation
Requirement depends on chilled water temperature and dewpoint
Overall HVAC cost increase = $300,000 compared to VAV

111. Construction Costs Reduced height
Floor heights reduced 10”-14”
Overall height reduced by 6’

112. Construction Costs Savings due to reduced height
Overall cost neutral
Pricing provided by CD Smith Construction

113. Viterbo
School of Nursing, WI

114. Rule # 5
When budgeting chilled beams, consider the overall 1st cost, not just the Mechanical vs VAV.