1. Munters DOAS and Chilled Beams
Presented by: Scott McGinnis Regional Sales Manager LEED® Associate

2. Overview Chilled Beam Systems Moisture Control
Munters Options Equipment

4. Whole Goal is to design a system where the Chilled Water temperatures throughout the building are consistent with the needs of the chilled beams and not driven by the OAU.

5. Active Chilled Beams

6. Neutral or Cold Air to Space Direct DOAS Design
Advantages:
Easier to measure the amount of outside air brought into the building (positive pressure).
Easier to assure the outside air reaches the occupied zones.
Dedicated ventilation diffusers allow easy airflow balancing (positive pressure).
No outside air load is imposed on the terminal units.
The space terminal units can be turned off when the space sensible load is satisfied.

7. Reasons For Chilled Beam
Chilled Beams use ~57F Entering Water Temps

8. Reset Chilled Water up
Energy Efficiency Manual

9. Reasons For Chilled Beam

10. Reasons For Chilled Beam

11. Calculating Building Moisture Load is More Important
Size the DOAS to handle ALL the Internal Latent Load
Prevents Chilled Beams from Sweating
#1 Fear of Design Engineers I have spoken with
Provides proper space %rh
Delivered Sensible Temp to Beam effects the beams capacity

12. Calculating Building Moisture Load is More Important

13. Typical Buildings & DOAS Designs (does not handle the indoor humidity load)
Space Served
Dew Point
Control
Meeting Space
Single
51-55 F
Loose
Grocery Store
48-52 F
Medium
Pharmaceutical
49-56 F
Tight
Hotel / Condo.
Multiple
54–56 F
Office
52-55 F
Classrooms
Healthcare
Depends
42-52 F
These outside air dew point design conditions do not take care of any of the indoor humidity loads. If the specialized outside air unit does not handle all or some of the space humidity load, then the space air conditions may still need to be improved to properly dehumidify the space.

14. How Dry Does the OA need to be?
ASHRAE shows how to calculate how DRY the OA needs to be in order to control space moisture.
If you want to maintain 75°F at 50%rh, then the space is at 55°F dewpoint.
You need to deliver air dryer that 55°F dewpoint.

15. Use the Correct OA Condition
106 gr/#
131 gr/#

16. Internal People Load vs Ventilation
QL = 1 person = 200 btu/per
Ventilation Required
15 CFM per Person
Capacity
What dewpoint air at 15 cfm will absorb all the moisture given off by a person sitting at rest?

17. Math Ventilation Air: 15 cfm x 30 students = 450
(6, ,150*) btuh = 450 x .68 x Delta Grains
8,150 = 306 x Delta Grains
8,150 / 306 = 26.6gr/#
Dewpoint of 450 cfm OA to achieve:
75°F/50% (55Fdp) = 42°F
75°F/55% (58F dp) = 45°F
75°F/60% (60F dp) = 49°F
Lower than the past
The Munters Story
Munters Products
*1600 btu/h = Simple Formula for Infiltration for standard classroom in 136 gr/# OA environment

18. Amount of OA?
The greater the amount of OA, the higher the dew point can be
The lower the amount of OA, the lower the lower the dewpoint
If we mix RA with OA, then the same rules above apply

19. Conventional Options
Coil Tonnage is large for Lower Dew Points

20. What to Offer with Chilled Beams
Chilled Beams want 57-60F water in the coils
DOAS needs low Dew Point air, thus needs low temp water
Thus typically uses a coil with low chilled water temps; 42-45F EWT
Is there an advantage of using just 57F water in the DOAS?
2x ?
42F to DOAS
60F to Chilled Beams
Or one large chiller making 42F water and reheating that for the beams

21. ASHRAE Journal, Jan 2012

22. ASHRAE Journal, Jan 2012 Higher Space RH approach
This approach is to use just a chilled water coil at standard coil conditions, maybe a little lower, i.e. 52F off the coil
To make this work, recommends raising space min % rh in order to raise the space dew point. Saying higher %rh is space = no need for lower delivered dew points
This seems to be as an attack on Desiccant, specifically Semco Pinnacle
FW owns Semco and thus have a package they promote
I personally feel trying to convince engr to raise the %rh floor will only help stifle the grown of chilled beams

23. This 45gr/# delivered system requires a Chilled Water Coil Delivering 52.7F Dry Bulb air: EWT = 45F
Why use 45F water for this unit and 57F for chilled beams?

24. Chiller Efficiency
Big Difference between 42F water and 60F water

25. Chiller Efficiency Big Difference between 42F water and 60F water
42F Chiller
32% Lower Op Cost
60F Chiller

26. Show the benefit of using High Temp water in the OAU and the Beams
DryCool Process allows this
DryCool Standard
DryCool Plus
3 Fan dryCool ERV
Custom DryCool
All systems above use no chilled water or water with equal temperatures to chilled beam coil water
Saves on chiller tonnage, and operating cost

27. 120F
OA/RA OA
47 gr/#
86 gr/#

28. HCUc: NO Chilled Water
Air
Water
46F DP
16 EER

29. Chilled Water DryCool: Higher Chilled Water
63F 57F F dp

30. How to Use DryCool With Energy Recovery?
If Possible, use the DryCool ERV or 3 Fan DryCool
No Need to Run Chilled Water to the DOAS
Delete Pumps, Piping, Piping Insulation and such to unit.
Down size Chiller plants for just the Chilled Beams and keep them at 60F water

31. Total Tons: CW (56) + DX (84) + Post (13) = 153 Tons
57F
82F/80Gr
Dry Air
57F
After E Wheel
69/44Gr
65F/80Gr
56F/61Gr
Total Tons: CW (56) + DX (84) + Post (13) = 153 Tons
Semco was at 156 Tons but required 45F Chilled Water

33. Semco 182”w x 146”h x 448” L

34. Enhanced Leaving Dew Point Control
DryCool Standard and DryCool ERV
Place a digital scroll compressor in the B position for modulating coil temp
Set a discharge are dew point control
Comp A is always on, but after that we can control pretty tight to DAT dew
Chilled Water HCU
By Modulating the Chilled Water coil we can control the leaving air Dew point
Space control
Monitor and control to the worse case space:
Unit staging will fluctuate, may be some risk if dramatic moisture swings

35. Leaving Air Post Cool Coil
Most cases the DryCool system will deliver supply air warmer than wanted
Add a Chilled Water Post cool coil and set to leaving air conditions
Use Chilled Beam water temps
Munters can control

36. Passive DH depends on what is uncontrolled

37. Plan of Action for Chilled Beam
Calc latent loads: Add those items not typically included
People, Infiltration, Permeance
DOAS equipment should take care of entire latent load
How much OA will be bring be processing?
DryCool Process: Drive the Moisture out of the DH Wheel
KEEP CHILLED WATER TEMP UP!
Benefits of one simple chiller plant with 58-60F water
By using all package DX
By using Hybrid of Chilled Water and DX with DryCool
Use a standard product if possible
Quicker selection
Better price points
Talk to factory about custom version to meet the engineers and owners needs
Discharge air temps, control
Layouts

38. Conclusion Chilled Beams do not need typical cold chiller water
Use of DryCool Process can eliminate or raise chilled water temps
Keeps chiller plant tonnage down
Keeps chiller electrical use down
Monitors and keeps Space moisture in check
Small buildings (small section of buildings, additions, etc):
DryCool Standard rio DryCool ERV
Medium Buildings
DryCool ERV or Custom HCU
Larger Buildings
Custom HCUs

39. Regional Sales Manager
Questions???
Saving the planet,
one LESS btu at a time
Scott McGinnis
Regional Sales Manager