Williams DH70 Manual

1
Model DH70, DH90 & DH125
Dehumidifier Installation, Operation
and Maintenance Instructions
INSTALLATION BY A HVAC PROFESSIONAL IS RECOMMENDED
This whole house dehumidifier can be used to control humidity in a
single area (standalone) or integrated into the heating and cooling
system to provide comfort, health and property protection.
READ AND SAVE THESE IMPORTANT
SAFETY INSTRUCTIONS
HVAC Installer: Please Leave Manual for Homeowner
Serial No: Install Date:
Sold by:

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TABLE OF CONTENTS
Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 - 4
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
General Operation
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Location considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Set Up Dehumidifier for Installation
Ducting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . .7
Dampers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Unit mounted Dehumidistat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Optional remote Dehumidistat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Frost Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Drain Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Float Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Leveling . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Condensate Pan, Condensate Pump and Float Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .8
Electrical
Circuit Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Installation Options
Ducting for Stand Alone Installations or Non-Ducted Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Wiring the Dehumidifier to the HVAC System
Independent mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .11
Dependent mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Ducting to HVAC System
Independent Operation mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Dependent Operation mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Basement or Attic installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Closet installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Start Up and Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Troubleshooting Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Service Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

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SAFETY INSTRUCTIONS
READ THE INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
CAREFULLY BEFORE INSTALLING AND OPERATING THIS DEVICE. PROPER
ADHERENCE TO THESE INSTRUCTIONS IS ESSENTIAL TO OBTAIN MAXIMUM BENEFIT
FROM YOUR WHOLE HOUSE DEHUMIDIFIER.
WARNING
THIS SYMBOL MEANS IMPORTANT INSTRUCTIONS. FAILURE TO HEED THEM CAN
RESULT IN SERIOUS INJURY OR DEATH.
CAUTION
READ ALL INSTRUCTIONS BEFORE BEGINNING INSTALLATION.
USE CAUTION AND WEAR CUT RESISTANT GLOVES WHEN HANDLING SHEET METAL, CUTTING
PLENUM OPENINGS AND HANDLING DUCT WORK. SHARP EDGES MAY CAUSE SERIOUS INJURY
FROM CUTS.
DEHUMIDIFIER IS HEAVY, DROPPING UNITMAYCAUSE PERSONAL INJURY OR EQUIPMENT
DAMAGE. HANDLE WITH CARE AND FOLLOW INSTALLATION INSTRUCTIONS.
THIS UNIT IS TO BE INSTALLED INDOORS IN AN AREA PROTECTED FROM RAIN OR MOISTURE.
INSTALLATION, SERVICE, AND MAINTENANCE MUST BE PERFORMED BY A QUALIFIED
SERVICE TECHNICIAN IN COMPLIANCE TO ALL LOCAL AND NATIONAL CODES. IMPROPER
INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE OR MAINTENANCE MAY CAUSE
PROPERTY DAMAGE OR INJURY.
DO NOT USE IN OR AROUND POOL OR SPA APPLICATIONS. POOL CHEMICALS CAN DAMAGE
THE DEHUMIDIFIER.
DO NOT USE SOLVENTS OR CLEANERS ON OR NEAR THE CIRCUIT BOARD. CHEMICALS CAN
DAMAGE CIRCUIT BOARD COMPONENTS AND CAN CAUSE PROPERTY DAMAGE OR
PERSONAL INJURY.
CAUTION
THIS SYMBOL MEANS IMPORTANT INSTRUCTIONS. FAILURE TO HEED THEM CAN
RESULT IN INJURY OR MATERIAL PROPERTY DAMAGE.
WARNING
120 V O LT S M A Y C AU S E S E RI OU S I N J U R Y FR O M E L E CTRIC S HO C K . D I S C ONNE CT
E L E CTRIC A L PO W E R BE F O R E S T A RTI NG I N S T A LL A TI ON O R S E R V ICI NG, AND LEA V E
PO W E R D I S C ONNE CT ED UN TIL I N S T A LL A TI ON OR S E R V IC E I S C O M P L E T ED .

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CAUTION
NEVER OPERATE A UNIT WITH A DAMAGED POWER CORD. IF THE POWER CORD IS DAMAGED,
IT MUST BE REPLACED BY THE MANUFACTURER, ITS SERVICE AGENT, OR A SIMILARLY
QUALIFIED PERSON IN ORDER TO AVOID A HAZARD.
FOR PROTECTION OF THE COMPRESSOR, IT MUST BE TRANSPORTED AND INSTALLED IN AN
UPRIGHT POSITION. IF THE UNIT WAS SHIPPED OR STORED ON ITS SIDE, A 24-HOUR
SETTLING PERIOD IN THE UPRIGHT POSITION IS REQUIRED BEFORE RUNNING THE UNIT FOR
THE FIRST TIME. TEMPORARY STORAGE MUST BE INDOORS, UPRIGHT IN THE ORIGINAL
CARTON, AND COMPLETELY SHIELDED FROM PRECIPITATION.
THIS APPLIANCE IS NOT INTENDED FOR USE BY PERSONS (INCLUDING CHILDREN) WITH
REDUCED PHYSICAL, SENSORY OR MENTAL CAPABILITIES, OR LACK OF EXPERIENCE OR
KNOWLEDGE, UNLESS THEY HAVE BEEN GIVEN SUPERVISION OR INSTRUCTION
CONCERNING THE USE OF THE APPLIANCE BY A PERSON RESPONSIBLE FOR THEIR SAFETY.
CHILDREN SHOULD BE SUPERVISED TO ENSURE THAT THEY DO NOT PLAY WITH THE
APPLIANCE.
SPECIFICATIONS
DH70
DH90
DH125
Capacity: Pints per day @ 80°F DBT / 60% RH
70
90
125
Unit Power Supply
120 Volts / Single Phase / 60 Hz
Minimum Branch Circuit / Max Fuse size
15 Amp
15 Amp (Single Outlet)
or 20 Amp
Rated Total Current
6.5
7.0
10.0
Dimensions
Cabinet Length:
25.25”
25.25”
24”
(includes duct collars)
31.38”
31.38”
30.25”
Cabinet Width:
14”
14”
25.25”
Cabinet Height:
15.62”
15.62”
20.75”
Weight: Pounds
81
82
128
Compressor:
Rotary Type
Watts
730
790
1190
RLA / LRA
6.7 / 42
7.15 / 32.5
10.5 / 55
Refrigerant
R410A - Oz
23
27
40.6
Fan Motor
HP / RLA
.08 HP / .60 RLA
.08 HP / .60 RLA
.12 HP / .85 RLA
Air Flow: CFM vs ESp
0” ESp (w.c.)
245
245
450
.5” ESP (w.c)
120
120
275
Filter
Washable Nylon
10.25” x 13.75”
10.25” x 13.75”
16” x 25”
Inlet Air Conditions
Dehumidification
50°F –104°F, 40°F dew point minimum
Duct Connections
8” diameter
Drain Connection
1/2” Vinyl tubing to 3/4” MPT
Max condensate pumping height
42”
* All specifications and performance data are subject to change without notice .

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GENERAL OPERATION
The function of your dehumidifier is to reduce the indoor humidity levels and increase comfort. It is a high
capacity dehumidifier able to remove up to 125 pints of water per day (80°F DBT / 60% RH). An internal
humidity sensor (dehumidistat) senses when the relative humidity (RH) is above the set point (example: 50%
RH) and signals the dehumidifier to operate until the relative humidity level has been lowered to the set point.
If the dehumidifier is located outside of the area where humidity control is desired, the unit can be configured to
use a remote dehumidistat (purchased separately) that is located in the area where humidity control is desired.
Locate the sensor where it can accurately sense the humidity of the area where control is desired.
The dehumidifier can be set up as a stand-alone unit that operates separately from the dwelling’s HVAC system.
In this type of installation the dehumidifier is not ducted to the HVAC system and is used to dehumidify a specific
area. This installation is typically used for basements/ crawl spaces, attics or rooms with high moisture problems.
The dehumidifier can also be set up to be inter-connected into the dwelling’s HVAC system. In this type of
installation the dehumidifier is ducted to the HVAC system and used to dehumidify the area served by the
dwelling’s HVAC system. When connected to the HVAC system, the dehumidifier can be configured so that the
dehumidifier and the HVAC system fans will operate separately of each other (Independent Operation mode) or
may be configured to require that the dehumidifier and HVAC fans operate at the same time (Dependent
Operation mode).
In cool damp climates, where the HVAC system runs infrequently or for short periods, Independent Operation
mode is the preferred mode of operation. The short cycle times of the HVAC system, while keeping the
temperature in control, does not effectively control the humidity level (not enough time to remove the excess
humidity from the dwelling). Independent Operation mode will allow the dehumidifier to continually monitor the
humidity level and operate as needed whenever the HVAC system is not running, working with the HVAC system
to maintain temperature and humidity control.
In warm/hot humid climates where the HVAC runs frequently or for long periods, Dependent Operation mode is
the preferred mode of operation. The long run time of the HVAC system will remove / control some of the excess
humidity with the dehumidifier removing the rest. In the Dependent Operation mode, the dehumidifier will monitor
the humidity level when the HVAC system fan is running and will turn on whenever the humidity level exceeds the
set point, removing the excess humidity as needed.
Standalone mode: See page 10 for details.
Independent mode: See page 11 for details.
Dependent mode: See page 12 for details.
UNPACKING AND CONTENTS
Do not tip unit to remove from carton.
Open carton completely using cut line marked along bottom perimeter of carton.
Remove all cardboard and inner pack from top edges and duct collars.
Carefully remove unit from carton bottom and inspect for any shipping damage.

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LOCATION CONSIDERATIONS
IMPORTANT PRECAUTIONS
Install Unit Indoors: The device is designed to be installed indoors in a space that is protected from rain
and flooding. Do not expose to elements. Do not use in pool or spa areas.
Location. When choosing an installation location, consider the accessibility for service, condensate drain
availability and power connection.
•When used as a stand-alone unit, avoid directing the discharge air at people.
•When the unit is to be inter-connected in the HVAC system, proper location is very important as it
will determine the overall length of the connection ducts. Locate the unit as close as possible to
the indoor portion of the heating or air conditioning system. The dehumidifier may be placed
above, below or level with the heating or air conditioning system.
•Allow sufficient clearance to handle the unit’s overall dimensions, with enough space to access all
sides for maintenance and service, as well as the necessary return and supply ductwork to the unit.
•Allow sufficient clearance for filter removal and to prevent airflow obstruction.
•Locate the unit in an area where field wiring the control (low voltage) to the unit will be possible.
DO NOT use the dehumidifier as a bench or table.
Mounting:DO NOT place the dehumidifier directly on structural building members without vibration
absorbers or unwanted noise may result. The dehumidifier may be mounted on a flat surface or suspended.
•If mounted on a flat surface, use the four rubber mounting feet provided. To minimize unwanted
vibration, select a level mounting surface. Adjust the mounting feet to compensate for any
surface irregularities. Make certain that the unit is sitting on all four mounting feet.
•To suspend the unit, a separate hanger kit (HD18 for the DH70 or DH90 models, HD19 for the
DH125 model, or suitable alternative) is required. This kit consists of two brackets and four
rubber isolators. Threaded rods or other means of suspension must be provided by the installer
and must be selected based on the unit weight and in compliance with local codes.
Drain Accessibility: If a floor level drain is not located in the installation area, the condensate pump in the
unit can drain water up to 42” above the base of the unit. Limit total length of drain line to 20’ from unit.
Power: Locate the dehumidifier in an area where the cord’s length (9') easily reaches a 120 VAC electrical
outlet with a minimum of a 15 Amp circuit capacity.
Filter Access: Allow for 22” clearance for removal of filter. Filter is removable from either side of unit.
Inlet: If the air inlet is not ducted, a minimum of 6” of open space is required from the inlet opening to an
adjacent surface.
Allow for proper drainage and routing of any needed drain pipes.
It is recommended a drain pan be placed under the unit if installed above a living area or above an area
where water leakage could cause damage.
It is recommended that a backdraft damper be used in the discharge duct of the dehumidifier, especially when
connecting to the supply ducting system. The backdraft damper prevents supply air from counter flowing
through the unit when it is not operating. The dehumidifier’s location should be chosen to allow installation of
this accessory if necessary.

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CAUTION
All duct connections must be sealed. Any air leakage in the duct work will adversely
affect the operation of the dehumidifier and may lead to unsatisfactory performance.
SET UP DEHUMIDIFIER FOR INSTALLATION
DUCTING
The unit is furnished with two beaded 8" round collars for duct connections to the inlet and the outlet of the
dehumidifier. The screened inlet and outlet duct collars are factory installed for horizontal airflow. The screens will
prevent entry of debris and small animals / insects.
Insulated flexible ducts in compliance with Underwriter’s Laboratories (UL) Standard for Factory Made Duct
Materials, UL-18 and installed per the duct manufacturer’s recommendation should be used to connect the
dehumidifier to the heating or air conditioning system. The installation and connections must be in compliance
with national and local codes and be completely tight and leak free. Ducts should be as short as possible, not to
exceed 100 ft. equivalent length and supported in compliance with the duct manufacturer’s recommendation.
•If necessary, the outlet duct collar may be moved to the top of the unit for vertical discharge of the airflow. For
the DH70 & DH90, remove the screws and swap the top panel with the outlet duct collar panel, the panels are
interchangeable. For the DH125, remove the round plate from the top and the duct collar from the end panel.
Mount the duct collar to the top and the cover to the end panel.
•Make sure there are no bends within 6” of the unit in the ductwork coming to or leaving from the unit. This will
ensure that the air flows freely through the unit.
•In freestanding applications (attic, basement, large single room), it is recommended to maintain a separation
of 10’ between the inlet and discharge of the unit, this is to prevent short-circuiting of the air and reducing the
effectiveness of the unit. This can be done by using a 5’ duct on both the inlet and discharge end of the unit,
or by a single 10’ duct on the inlet or discharge end.
DAMPERS
Optional dampers may be installed in the outlet duct, inlet duct or in an outside air duct. These dampers must be
a full-flow motorized type. Do not use any type of pressure operated damper as unacceptable pressure drop will
affect unit operation. All dampers must be installed in compliance with the damper manufacturer’s
recommendations and be insulated and sealed per the section on ducting above.
UNIT MOUNTED DEHUMIDISTAT
The unit is controlled by the integral control system which operates the internal fan approximately 15 minutes
each hour to sample the air in the system. The air sample passes over the unit-mounted humidity sensor which
should be set at approximately mid-level. After a three minute delay, if the humidity level in the sampled air is
greater than the set point, the dehumidifier will turn on. The dehumidifier will operate until the humidity level is
less than the sensor set point.
OPTIONAL REMOTE DEHUMIDISTAT
The unit may also be controlled by HD16, a dehumidistat remotely located in a conditioned space. Do not locate
the remote dehumidistat in the HVAC system ductwork. It is recommended that dehumidistat be located in an
area close to the heating or air conditioning system thermostat, out of drafts, away from heat sources and out of
direct sunlight. It should be located approximately five feet above the floor in an area with good air circulation at
an average temperature and relative humidity.

8
SET UP DEHUMIDIFIER FOR INSTALLATION (CONTINUED)
When a remote dehumidistat is used, the unit-mounted control must be set to the lowest relative humidity (RH)
setting and never readjusted. The remote dehumidistat should be set in the comfort area of approximately 50%
relative humidity. When the dehumidistat senses that the relative humidity in the space is above its set point, an
electrical contact within the dehumidistat allows the dehumidifier to start. The unit operates until the relative
humidity has been lowered to the set point.
Remove the jumper on terminals S1 and S2 and connect the remote dehumidistat as shown on the unit
connection schematic.
FROST CONTROL
In some cases of prolonged operation or if the conditioned space is relatively cool, frost will accumulate on the
coil. Ice may eventually cover the coil, block the air flow and stop proper operation. If the coil becomes
unacceptably cold for at least ten minutes, a sensor mounted on the coil will stop the compressor. To prevent
frost build-up beyond an acceptable level, the fan will continue to operate to melt any accumulated ice. Once the
ice has melted and the coil is warm, the compressor will restart and the dehumidification process will resume.
DRAIN INSTALLATION
The DH70, DH90 and DH125 units use an internal condensate pump to drain the water that is removed from the
air. The pump will operate as needed, which may be frequently if the air is more humid than normal or less
frequently if drier. Use the provided fittings and 1/2” clear PVC tubing to drain the water from the dehumidifier.
The pump can discharge the condensate into a drain located up to 42” higher than the bottom of the unit.
FLOAT SWITCH
In addition to the condensate drain line, the unit is equipped with a float switch. If the drain line should become
clogged or restricted, overflow of water could occur. To prevent this, the float switch disables the unit’s
compressor and fan to stop water production. The red indicator light located near the dehumidistat knob will turn
on, indicating that the drain has become clogged. Once the blockage has been cleared, the power supply to the
unit must be switched off and then back on - the switch will then allow the unit to return to normal operation.
LEVELING
The feet can be adjusted to level the unit, and if required, to accommodate secondary condensate pan. Leveling
is required to ensure proper drainage from the dehumidifier.
CONDENSATE PAN, CONDENSATE PUMP AND FLOAT SWITCH
It is highly recommended that a drain pan be placed under the unit if installed above a living area or above an
area where water leakage could cause damage. Adhere to local codes regarding draining of the condensate from
the pan. If a condensate pump is needed, install it in the drain pan as well.

9
WARNING
Turn off electrical power at the fuse or service panel before making any electrical connections.
Failure to do so can result in electrical shock, severe personal injury or death. The dehumidifier
must be installed so that the electrical components are protected from water from any source.
ELECTRICAL
WARNING
ELECTRICAL SHOCK HAZARD: 120-volts may cause serious injury
or death from electrical shock. Disconnect and tag electrical service
before starting installation or field-service. Leave electrical service
disconnected until installation or field-service is complete.
ELECTRICAL SHOCK HAZARD: An interrupted or broken ground
may cause property damage, serious injury or death should an
electrical fault occur. The cabinet must be grounded in accordance
with NEC ANSI/NFPA 70-2011 or local codes. In Canada, refer to
Canadian Electrical Code CSA C22.1.
FIRE HAZARD: Use of improper wire may cause serious injury,
property damage or death due to fire. Do not use aluminum wire for
electrical service to the dehumidifier. Use only copper wire.
CAUTION
Use of an undersized circuit
breaker may cause property
damage and/or the need for
mold remediation service. See
Specifications for wire and
circuit breaker sizing.
Installation must be performed by a qualified service technician and must comply with all national and
local codes. Remove power to the device before installing or servicing the equipment.
The dehumidifier is supplied with a 9 foot long 3-prong grounded power cord and is intended to be connected to a
dedicated, grounded branch electrical circuit containing a properly sized fuse or circuit breaker. This circuit must
run directly from the main circuit box to an electrical receptacle located within 6 to 8 feet of the intended location of
the unit. This receptacle must be readily accessible or located as needed to comply with appropriate national or
local codes or ordinances.
United States Installations: Make all electrical connections in accordance with the current edition of the NEC
ANSI/NFPA 70 and any local codes or ordinances that may apply.
Canada Installations: Make all electrical connections in accordance with the current edition of the Canadian
Electrical Code CSA C22 .1 and any local codes or ordinances that may apply.
ELECTRICAL SPECIFICATIONS
Model DH70 & DH90
Model DH125
Voltage / Freq. / Phase
110-120 VAC / 60 / 1
Minimum Circuit Requirements - Amps / Wire size
15 A / 14 AWG
15 A / 14 AWG
Dedicated circuit or
20 A / 12 AWG

10
Installation Options
STAND ALONE OR NOT DUCTED TO HVAC SYSTEMS
In this installation the dehumidifier is not ducted to the HVAC system and is used to dehumidify a specific area.
This installation is typically used in basements, attics or crawl spaces.
Optional Components
8” Ductwork - use insulated ductwork when dehumidifier is located in an unconditioned space (attic, garage)
Grilles with 8” Duct Collars
•The unit can be located adjacent to, above or outside of the area to be dehumidified, with ducting used to
bring air from the space to be processed then returned to the space (see below).
•In freestanding applications (attic, basement, large single room), it is recommended to maintain a separation
of 10’ between the inlet and discharge of the unit, this is to prevent short-circuiting of the air and reducing the
effectiveness of the unit. This can be done by using a 5’ long duct on both the inlet and discharge end of the
unit, or by a single 10’ long duct on the inlet or discharge end. Secure end of duct(s) to prevent movement.
•Make sure there are no bends within 6” of the unit in the ductwork coming to or leaving from the unit. This will
ensure that the air flows freely through the unit.
Mounted in Drop Ceiling