CDQ
™
dehumidification
Cool, dry, quiet with Trane rooftop units
Trane CDQ™ removes more water
per ton of cooling with no field
modifications.
Rooop unit
Outside air
Mixed
air
LVG regen
Return air
LVG RTU
Supply air
Curb with Trane CDQ
The Trane CDQ™ desiccant wheel is used to
enhance the dehumidification performance of a
traditional cooling coil. The wheel is configured
in series with the coil (see RTU Airflow Path
illustration) such that the “regeneration” side
of the wheel is located upstream of the coil
and the “process” side of the wheel is located
downstream of the cooling coil. The wheel
recirculates the water vapor trapped
downstream of the cooling coil back into
the air upstream of the coil where the coil
removes it through condensation.
200%
Latent Capacity
150%
100%
50%
Latent capacity increase
0%
35%
45%
55%
Return air relative humidity
55% more dehumidification at ARI conditions
Heat removed
Heat removed
46 MBH
Standard 5 ton RTU
SHR = 0.74
Water removed
1.8 GPH
37 MBH
Standard 5 ton RTU + CDQ
SHR = 0.74
For units with less that 40 percent outside air,
CDQ can greatly improve the latent capacity of
the unit. This results in a lower sensible heat ratio
(SHR) without the addition of reheat.
65%
Water removed
2.9 GPH
This process is accomplished without the
Developed in collaboration with the U.S.
Department of Energy through Oak Ridge
need for a second regeneration air stream.
National Laboratory.
The addition of the CDQ desiccant wheel to
the system enhances the dehumidification
performance of the traditional cooling coil.