Installation and Operation Manual -
WHDEHUM-90P
4
Operating Modes/Configurations
The Comfort-Aire/Century WHDEHUM-90P
supports whole-house dehumidification and
standalone unit dehumidification modes for
crawlspace and basement applications.
Standalone Unit Dehumidification
Standalone Unit Dehumidification (SUD) is typically
used to dry basements and crawlspaces. For
this application, the WHDEHUM-90P is capable
of operating in a complete standalone mode in a
ductless configuration that does not require any
extra ducting or control system hook-ups. In SUD
mode, the unit has an integrated humidistat and
controller. The user just connects power, plumbs
in the water drain, turns the unit on, configures the
unit control for SUD mode, then sets the desired
humidity and leaves it alone. Thereafter, the unit
automatically senses the humidity level and turns
on as needed to remove access moisture in the air.
Whole-House Dehumidification
There are two whole-house dehumidification
configurations that can be addressed with
the WHDEHUM-90P. In the first of these
configurations (see Figure 1, page 4), the
dehumidifier serves the whole house but is not
duct-integrated with the HVAC system. Secondly,
the unit shares the return and supply ducting of
the HVAC system and may even share a common
integrated thermostat/humidistat (see Figure 2A
and 2B, page 4).
Separate Duct Systems
Whole-house separated dehumidification systems
have traditionally been utilized to support separate,
more isolated rooms that require dehumidification.
As of late, there is a growing trend towards mini-split
HVAC systems that are implemented as heating
and cooling systems. Separated dehumidification
configurations are ideal solutions for mini-split based
HVAC systems.
Separate duct systems operate independent of
the HVAC system and are located in basements,
crawlspaces, or perhaps in a closet with ducting to
and from the living area to be humidified.
HVAC Duct Systems
Whole-house HVAC duct systems are
dehumidification configurations in which
the WHDEHUM-90P will be directly duct-
interconnected with the home’s central HVAC
system and typically share control elements
to ensure that the units properly functions with
the ducted airflow. Below are the likely system
example drawings of HVAC configurations.
The dehumidifier can be installed in a variety of lo-
cations to meet the owner’s needs as listed below.
In all cases, keep the following cautions in mind:
1.
The unit is designed to be installed indoors in
a space that is protected from rain, flooding,
and/or other forms of excess water. Unit is not
designed to be exposed to chlorinated pool
conditions or corrosive chemicals or conditions.
2.
Install the unit with space to access the front
panel for maintenance and service. Also, allow
easy access to the filter cover panel.
3.
Avoid discharging the air directly at people,
over the water in pool areas, or other areas or
objects where dehydration or evaporation of
moisture is not desired.
4.
If used near wet areas, be certain there is NO
chance the unit could fall into the water or be
Figure 1.
Whole-Home Separate Duct System
Figure 2B.
Whole-Home HVAC Duct System
Figure 2A.
Whole-Home HVAC Duct System
Unit Location
