Quest Engineering 100 Manual

INSTALLATION, OPERATION AND
MAINTENANCE INSTRUCTIONS
QUEST
100
QUESTCLIMATE.COM / [phone]
Patents: thermastor.com/patents
Serial Number
Install Date
Sold By
06/23 REV A
Compact Size
Digital Controls
Industry-Leading Efficiency
Superior MERV-13 Air Filtration
Ducting Options for Divided Spaces
Auto-Restart After Power Outages
CALIFORNIA
TITLE 24 COMPLIANT

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
QUESTCLIMATE.COM(877) 420-1330
TABLE OF CONTENTS
Safety Precautions............................................................3
1. Intended Application....................................................4
2. Registrations .................................................................4
3. Specifications................................................................4
4. Installation .....................................................................5
4.1 Location...................................................................5
4.2 Ducting...................................................................5
4.3 Condensate Water Removal ...............................9
4.4 Hanging Diagram ............................................... 10
4.5 Electrical Requirements.................................... 11
Control Options................................................................ 12
5.1 (A) Onboard Dehumidistat ................................ 12
5.1 (B) External Control Options ............................ 13
5.2 External Control.................................................. 14
6. Maintenance ................................................................ 14
6.1 Standard Air Filter............................................... 14
6.2 Impeller Fan Oiling ............................................. 14
7. Service.......................................................................... 15
7.1 Warranty................................................................. 15
7.2 Technical Description......................................... 15
7.3 Troubleshooting................................................... 15
7.4 Refrigerant Charging.......................................... 17
7.5 Impeller Fan Replacement................................. 17
7.6 Compressor/Capacitor Replacement .............. 17
7.6A Checking Compressor Motor Circuits ... 17
7.6B External Control Options ......................... 18
7.6C Replacing Compressor-Nonburn Out..... 19
7.7 Remote Controls.................................................. 19
7.7A Humidity Control ....................................... 19
7.8 Defrost Thermostat ............................................. 19
7.9 Condensate Pump Kit.......................................... 19
7.10 Power Cord Replacement................................. 20
Error Codes...................................................................... 22
Wiring Diagram.................................................................. 11
Service Parts List ........................................................... 24
Optional Parts List ......................................................... 24
Warranty......... .................................................................. 23
4201 Lien Rd. Madison, WI 53704
[phone]
Thermastor.com | QuestClimate.com
© 2016 Therma-Stor LLC

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
QUESTCLIMATE.COM(877) 420-1330
SAFETY PRECAUTIONS
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 Quest Dehumidifier.
READ AND SAVE THESE INSTRUCTIONS
• The device is designed to be installed INDOORS IN A SPACE THAT IS
PROTECTED FROM RAIN AND FLOODING.
• Install the unit with space to access the back or side panels for
maintenance and service. DO NOT INSTALL UNIT WITH THE SERVICE
PANELS INACCESSIBLE.
• Avoid directing the discharge air at people, or over the water in pool
areas.
• If used near a pool, spa or water; be certain there is NO chance the unit
could fall into the water, be splashed and that it is plugged into an outlet
that is a GROUND FAULT INTERRUPT protected circuit.
• DO NOT use the device as a bench or table.
• DO NOT place the device directly on structural members. Provide vibration
isolation in order to minimize operational vibration and/or noise.
• A drain pan MUST be placed under the unit if installed above a living area
or above an area where water leakage could cause damage
• 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
similarly qualified person in order to avoid a hazard.
• Make all electrical connections in accordance with the current edition of
the NEC ANSI/NFPA 70 and any national and local codes or ordinances
that may apply.
• Maintain a minimum 1ft. (.3m) clearance to avoid obstructing the air return
and supply.
• This appliance is not intended for use by persons (including children) with
reduced physical, sensory or mental capabilities, or lack of experience
and knowledge, unless they have been given supervision or instruction
concerning 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.
• Not intended for use at altitudes over 6500 ft (2000M).

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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1. INTENDED APPLICATION FOR QUEST 100
The Quest 100 Dehumidifier is designed to operate in temperatures between 56° and 95°F.
In order to efficiently control humidity levels, the area in which the dehumidifier is to be operated must
be free of water intrusion or excessive fresh (outside) air infiltration. Before installing the Quest 100
Dehumidifier, water intrusion and air infiltration problems should be addressed or noted in calculations.
2. REGISTRATIONS
The Quest 100 Dehumidifier units conform to unified standard UL 60100-2-40, CSA C22, 2#60100-2-40.
US Patents: D570,988 / 8,069,681 / 9,052,132.
3. SPECIFICATIONS @ 80°F/60% RH
UNIT QUEST 100
4041870
CFM: 280 @ 0.0” WG
POWER: 540 Watts
SUPPLY VOLTAGE: 120 Volt
1 Phase - 60 Hz
CURRENT DRAW: 5.0A
RATED CURRENT DRAW:
(104 F | 36%) 6.8A
MINIMUM CIRCUIT AMPACITY (MCA):8A
MAXIMUM OVERCURRENT PROTECTION
(MOP):15A
RECOMMENDED BREAKER SIZE: 15A
ENERGY FACTOR (L/KWH):3.55 L/kWh
OPERATING TEMP: 56 F Min – 95 F Max
WATER REMOVAL (PINTS/DAY):
EFFICIENCY (PINTS/KWH):
100
7. 5
AIR FILTER (MERV-13): Size: 12” x 14” x 1”
POWER CORD: 9’, 115 VAC, Ground
DRAIN CONNECTION: 3/4” Threaded NPT
REFRIGERANT TYPE:
REFRIGERANT AMOUNT:
R410A
1 lb 7 oz
DIMENSIONS:
WIDTH:
HEIGHT:
LENGTH:
WEIGHT:
Unit Shipping
24” 26.5”
14.5” 18.5”
16” 18.75”
60 lb 65 lb
4.5. Service ....................................................................... 11
*MCA = Minimum Circuit
Ampacity
This number provides a qualified
electrician with the information
needed to determine the minimum
wire size used in the circuit that
feeds a single dehumidifier.
* MOP = Maximum Overcurrent
Protection
This number provides a qualified
electrician with the value of the
maximum size circuit breaker that
may be used to protect the circuit
that feeds a dehumidifier.
Specifications are subject
to change without notice.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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4. INSTALLATION
4.1 LOCATION
The Quest 100 Dehumidifier can be installed in a variety of locations to meet the owner’s needs as listed
below. In all cases keep the following cautions in mind:
• Locate the dehumidifier near a suitable drain (8’ drain hose included). Allow for proper drainage and
routing of needed drain pipes.
• Locate the dehumidifier in an area where the cord’s length (9’) easily reaches a 115 VAC electrical
outlet with a minimum of a 15 Amp circuit capacity.
• The unit is designed to operate while level. If the unit is placed on an unlevel surface, refer to section
below (Installing Leveling Feet). Failure to level the unit may result in leakage or improper drainage.
• Allow sufficient clearance to handle the unit’s overall dimensions as well as any optional return and
supply ductwork to the unit.
• Allow sufficient clearance for filter removal and to prevent airflow obstruction.
• Electrical service access will require the removal of the top “L” shaped panel. Allow sufficient
clearance around the unit.
• The Quest 100 Dehumidifier may be suspended with steel hanger, straps, or a suitable alternative
from structural members, unit must be supported from underneath. Don’t hang from sides or ends.
See section 4.4
• The unit should be suspended with a hang kit from the floor joists if there is any possibility of
flooding. A flooded unit is not covered by warranty. Feet will be installed as a securing measure after
the hang kit is put on the dehumidifier. DO NOT hang the Quest 100 dehumidifier from its’ cabinet.
4.2 DUCTING
Return and supply duct collars are optional accessories for the Quest 100 and not included with the unit.
CAUTION! Do not connect with a static pressure greater than or equal to +1.0 WG. Contact
technical support at [phone] for additional details.
DUCTING CONSIDERATIONS:
•All flexible ducting connected to the Quest 100 should be UL listed.
• A short piece of flexible ducting on all Quest 100 duct connections is recommended to
reduce noise and vibration transmitted to rigid ductwork in the structure.
• Use a minimum 10” diameter round or equivalent rectangular duct for total duct
lengths of up to 25’.
• Grills or diffusers on the duct ends must not excessively restrict airflow.
• A length of 8” or more of insulated flex duct or any other vibration isolating material on the
outlet of the Quest 100 will reduce air noise from the blower.
• When ducting two or three areas, use 8” or larger diameter branch ducting. When ducting to four or
more areas, use 6” or larger diameter branch ducting. Provisions must be made to provide airflow
supply locations to the central return location. Proper air distribution is important to ensure even
humidity control and heat distribution throughout the structure.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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DUCTING TO HVAC OPTIONS
A. HVAC SUPPLY TO SUPPLY
CAUTION!
To avoid the dehumidifier cycling in and out of DEFROST, it is recommended that the leaving air temperature
of the A/C coil is not below 55°F. Also, this install is not recommended for climates where the heating
system will run during the spring and fall times of year, as this could diminish the water removal capability
of the dehumidifier. If the Check Damper is not used, it is important to have the HVAC system fan ON when
the dehumidifier is ON to prevent backflow of air.
WARNING! Due to pressure resistance it is not recommended to use the optional outdoor air
intake when installing the dehumidifier supply to supply.
B. DEDICATED RETURN TO SUPPLY
Quest 100
Indoor Air
Return
Air Handler Supply
Quest 100 Supply
Optional Duct
Tee & Gravity
Damper
HVAC
Supply
Quest 100
Return
Dry Air to
Conditioned Space
Quest 100
Supply
Air Handler
Optional Check Damper
(No HVAC fan needed)

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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CAUTION! PLEASE NOTE: Return to Return installs are to be considered last resort options and are not
recommended. The dehumidifier will heat the AC cooling coils which diminishes the amount of water the AC system
will remove when operating. If this installation is chosen, the dehumidifier must activate the HVAC blower and AC
calls need to lock out the dehumidifier from running. Please check your local codes prior to installing.
C. DEDICATED QUEST RETURN TO HVAC RETURN
Create a separate return for the
Quest 100 Dehumidifier in a central
area of the building.
Installing the supply air from the
Quest 100 Dehumidifier to the return
of the HVAC system requires the HVAC
fan to run when the Quest Dehumidifier
is operating.
D. HVAC RETURN TO HVAC RETURN
NOTE: If Check Damper is not in place,
the HVAC fan must ON when
the dehumidifier is in operation.
Quest 100 Indoor
Air Return
Quest 100
Return
Optional Outdoor
Air Intake
Optional Check Damper
(No HVAC fan needed)
HVAC
Return
HVAC
Return
Quest 100
Supply
Quest 100
Supply
Backdraft
Damper
HVAC
Supply
HVAC
Supply
Air Handler
Air Handler

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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E. HVAC RETURN TO HVAC SUPPLY
F. NO EXISTING DUCTWORK INSTALLATION
When installing the Quest 100 Dehumidifier in a structure that does not have a forced-air HVAC system,
a single return for the dehumidifier should be installed in a central location. The supply air should be ducted back
into the space you want to dry. Proper air distribution is important for optimal performance of the dehumidifier.
Install a 6” insulated duct from outside, teeing into the 8” return duct of the Quest 100 Dehumidifier
to provide outdoor air ventilation (optional).
An 8” diameter duct is recommended for branches to larger areas.
Check Damper should be in place
between the Return and Supply
connections of the dehumidifier.
If the Check Damper is not in place,
the HVAC fan must be ON when
the dehumidifier is in operation.
Anything greater than 0.4” of static
requires HI fan setting. Anything greater
than 0.7” of static requires HI override
(99). Anything greater than 0.9” is not
recommended.
Quest 100
Supply
Quest 100
Indoor Air
Return
Quest 100
Return
Quest 100
Supply
Quest 100
Return

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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A. If the provided drain hose does not reach your
drain, rigid PVC tubing is readily available
from your local hardware store. Be sure the
extension is at a downward slope to the drain.
B. An optional condensate pump kit may
be installed if lift is required to remove
condensate. To order, contact your local dealer
or visit our website at www.questclimate.com.
OUTPUT TO DRAIN OR BUCKET.
4.3 CONDENSATE WATER REMOVAL
NOTE: This unit is positively pressured and using a p-trap is not recommended.
*
Primary Drain Port
End View
Secondary Drain Port

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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4.4 HANGING DIAGRAM, QUEST 100
4036668
Hang Bracket
(PN 4036668)
Bottom view of dehumidifier
and two brackets (not included)
NOTE: LEVELING FEET HOLD BRACKETS IN PLACE

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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5.1 ELECTRICAL REQUIREMENTS
The Quest 100 dehumidifier plugs into a common grounded 115VAC outlet. The dehumidifier draws
5.0 Amps at 80 F and 60% RH. Locate the dehumidifier in an area where the cord’s length (9’) easily
reaches a 115 VAC electrical outlet with a minimum of 15 Amp circuit capacity. If used in an area that
may become wet, a GFCI protected circuit is recommended. The unit should not be used in areas
prone to flooding. Consult local electrical codes for any further information.
An optional remote dehumidistat is available for use with the Quest 100 dehumidifier and is to be
located remotely from the dehumidifier.
CAUTION! ELECTRICAL SHOCK HAZARD: Electrical power must be present to
perform some tests. These tests should be performed by a qualified service person.
WIRING SCHEMATIC
P/N 4042336 Rev. B
BLK-1
SERIAL SWITCH
PRESSURE
SWITCH
BLU-14
BLU-15
( )
( )
DISPLAY BOARD
(CLASS 2) (CLASS 2)
(CLASS 2)
(CLASS 2)
(CLASS 2)

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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6. CONTROL OPTIONS
The Quest 100 Dehumidifier can be controlled by its on board dehumidistat or with an external control
using its low voltage terminal block.
6.1A QUEST 100 ON BOARD DEHUMIDISTAT
Off Mode: Fan, Compressor, Display and all LEDs are off
To Turn Unit On: Press the power button
On Mode: Display is on and shows the set point (Initial set point: 55% RH)
To Change Set Point:
• Press the up or down arrow once, the 2-digit display will begin to blink.
• Adjust to desired RH. Each push of the button will change the SP 1% RH.
• After 6 seconds without a button being pushed the number showing will become the new SP
DEFROST LIGHT
• The light over the snowflake will light up when defrost is occurring (ice is detected on coils).
The fan will be on, and the compressor will be off during defrost.
FILTER RESET
• Filter reset button will light up after the fan has been running for 2,000 hours.
• After changing the filter, press and hold the filter reset button to reset the 2,000-hour timer. Light
flashes while button is held.
DARK MODE
• Press the Dark Mode button to activate Dark Mode.
• Once Dark Mode is activated, lights will remain on for 20 seconds before the unit’s hygrostat will
go dark. Dark Mode light will flash for 3 seconds before unit goes dark.
• Unit will temporarily leave dark mode when any button is pushed and will go dark 20 seconds after
the last button is pushed.
• To turn off Dark Mode, press the Dark Mode button and ensure light above Dark Mode button is off.
• This mode is for applications where the user would like the unit to operate without emitting any light.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
QUESTCLIMATE.COM(877) 420-1330
FAN
TERMINAL CONTROL
6.1B QUEST 100 EXTERNAL CONTROL OPTIONS
Quest offers three external control options: Quest DEH 3000R and Honeywell Humidipro.
NOTE: 12 ga wire needed for sensor.
To order, contact your dealer, call 1-877-420-1330, or go to:
www.questclimate.com/product-category/accessories
4028531 4041649
• When the Terminal Control button is pressed, the display will show “tc”.
• The Terminal Control button is used to activate the “DEHUM” input on the terminal
block. (see section 5.1B)
• This must be activated when an external control is used to control RH. When Terminal
Control is active, the internal RH sensor is disabled.
Pressing the Fan button alternates the unit between 3 fan speeds:
• (Hi)gh: Increased fan speed to be used exclusively in ducted applications. Deactivates filter-life
compensation mode.
• (Au)to: Default fan speed. Filter-life compensation mode active.
• (Lo)w: Decreased fan speed that lowers the volume and performance of the unit. Deactivates
filter-life compensation mode.
Changing Max Fan Speed
• Hold the FAN button for 3 seconds, the 2-digit display will begin to flash.
• Once the display is flashing, the maximum fan speed can be adjusted 1% at at time (in the
range of 60–99%).
• The new maximum fan speed can be locked by not pressing any buttons for 6 seconds or by
pressing the FAN button.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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6.2 QUEST 100 EXTERNAL CONTROL
Remove the cover from the user interface to expose the terminal block inputs & outputs.
Red Arrow (top): Float jumper wire MUST be stay in place or unit will go into error.
Blue Arrow (bottom): This is an extra jumper wire that has no function in its factory-installed location.
Move the wire up one spot to FAN and 24V for continuous fan operation.
Quest 100 Terminal Block Control Operations:
DEHUM: Dehumidification (Fan and Compressor) Control Input.
24VAC: Transformer High Side Output to External Control.
Fan: Fan Control Input.
24V COM: 24VAC Power Transformer Neutral Side Output to External Control.
FLOAT: External Low Voltage Float Switch or Water Sensor Input (Use Normally Closed Switch).
FLOAT: External Low Voltage Float Switch or Water Sensor Input (Use Normally Closed Switch).
Alarm: Normally Closed Relay Output - Indicates when dehumidifier is in an alarm state.
Alarm: Normally Closed Relay Output - Indicates when dehumidifier is in an alarm state.
NOTE: Alarm terminals are used to interface with a remote alarm or building automation
system. The terminals switch when the unit has a malfunction and are factory set to
“normally closed” but can be changed to “normally open”.
7. MAINTENANCE
WARNING! NOTE: Do not operate the unit without the filter or with a less
effective filter. The heat exchange coils inside the unit could become clogged and require
disassembly to clean. Filter non-compliance invalidates the product warranty.
6.1 STANDARD AIR FILTER
The Quest 100 Dehumidifier ships with a standard MERV 13 efficient pleated fabric filter. This filter should be
checked every six months. Operating the unit with a dirty filter will reduce dehumidifier capacity and efficiency
and may cause the compressor to cycle off and on unnecessarily on the defrost control.
To access the air filter, remove the filter access panel from the end of the Quest 100 Dehumidifier. The filter
should be readily visible and can be removed by pulling it straight out of the Quest 100 Dehumidifier.
We recommend changing the filter at least every 6 months. For agriculture we recommend changing the filter
with every grow cycle.
DAISY CHAIN

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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7. SERVICE
WARNING! Servicing the Quest 100 with its high pressure refrigerant system
and high voltage circuitry presents a health hazard which could result in death,
serious bodily injury, and/or property damage. Only qualified service people should
service this unit.
7.1 WARRANTY
A warranty certificate has been enclosed with this unit; read it before any repair is initiated. If a warranty
repair is required, call the factory first at 1-877-420-1330 for warranty claim authorization and technical
assistance.
7.2 TECHNICAL DESCRIPTION
The Quest 100 Dehumidifier uses a refrigeration system similar to an air conditioner’s to remove heat and
moisture from incoming air, and add heat to the air that is discharged.
Hot, high-pressure refrigerant gas is routed from the compressor to the condenser coil. The refrigerant
is cooled and condensed by giving up its heat to the air that is about to be discharged from the unit. The
refrigerant liquid then passes through a filter/drier and expanion device which causes the refrigerant
pressure and temperature to drop. It next enters the evaporator coil where it absorbs heat from the
incoming air and evaporates. The evaporator operates in a flooded condition, which means that all
the evaporator tubes contain liquid refrigerant during normal operation. A flooded evaporator should
maintain nearly constant pressure and temperature across the entire coil, from inlet to outlet.
The compressor collects the cool refrigerant gas and compresses it to a high pressure and temperature
to repeat the process.
7.3 TROUBLESHOOTING
Unit Test to determine problem:
1. Detach any exterior control wiring by removing terminal block but jump both FLOAT terminals
together.
2. Reinstall terminal block into the control.
3. Plug unit in to known good power outlet: 120 volts.
4. Power unit on by pressing power button on top of control.
5. Make sure the Terminal Control light is NOT illuminated. Press button to change.
6. Press down arrow to set the unit below 20% until “On” is displayed. This will force the unit on.
7. Listen for the fan to turn on almost immediately.
8. Wait 1 to 2 minutes for the compressor to turn on.
9. If these tests work, the problem is most likely in the control or field wiring.
Neither fan nor compressor running. Dehumidification is being called for. No fan call.
1. Unit unplugged or no power to outlet.
2. Humidity control set too high.
3. Loose connection in internal or control wiring.
4. Bad control or power board.
5. Defective control transformer.

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Compressor is not running. Dehumidification is being called for. No fan call.
1. Defective compressor run capacitor.
2. Loose connection in compressor circuit.
3. High pressure switch open or unplugged.
4. Defective compressor.
5. Compressor relay defective or unplugged.
6. Temp & RH sensor reading above 120 F or below 40 F, or sensor is bad or unplugged.
Compressor cycles on and off. Dehumidification is being called for. No fan call.
1. Low ambient temperature and/or humidity causing unit to cycle through defrost mode.
2. Evaporator temp sensor bad or unplugged.
3. Defective compressor.
4. High pressure switch defective.
5. Dirty air filter(s) or air flow restricted.
6. Bad control or power board.
Fan is not running. Dehumidification or fan is being called for.
7. Loose connection in fan circuit.
8. Obstruction prevents fan impeller rotation.
9. Defective fan.
10. Bad control or power board.
Low dehumidification capacity (evaporator is frosted continuously). Dehumidification is being called for.
11. Evaporator temp sensor bad or unplugged.
12. Low refrigerant charge.
13. Dirty air filter(s) or air flow restricted.
14. Excessively restrictive ducting connected to unit.
Unit removes some water, but not as much as expected.
15. Air temperature and/or humidity have dropped.
16. Humidity meter and or thermometer used are out of calibration.
17. Unit has entered defrost cycle.
18. Air filter dirty.
19. Low refrigerant charge.
20. Air leak (eg. loose cover or ducting leaks).
21. Defective compressor.
22. Restrictive ducting.
23. Unit is in (Lo)w fan mode.
24. Evaporator temp sensor bad or unplugged.
25. Temp and RH sensor off calibration. Reading lower than actual.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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Filter Change Light illuminated (too frequently):
1. Change filter if dirty.
2. Hold filter change button to reset filter life hours.
7.4 REFRIGERANT CHARGING
If the refrigerant charge is lost due to service or a leak, a new charge must be accurately weighed in. If
any of the old charge is left in the system, it must be recovered before weighing in the new charge. Refer
to the unit nameplate for the correct charge weight and refrigerant type.
7.5 IMPELLER FAN REPLACEMENT
The motorized impeller fan is a unitary assembly consisting of the motor and impeller fan. If defective,
the complete assembly must be replaced.
1. Unplug the power cord.
2. Remove the access panel, and top panel.
3. Disconnect the impeller fan leads on side of the electric box.
4. Remove fan/bracket assembly by removing two screws from the bracket and inlet ring assembly.
5. Remove the defective impeller fan from the bracket and replace with it with the new impeller fan.
7.6 COMPRESSOR/CAPACITOR REPLACEMENT
This compressor is equipped with a run capacitor, but no start capacitor or start relay.
7.6A CHECKING COMPRESSOR MOTOR CIRCUITS
Perform the following tests if the impeller fan runs but the compressor does not with a call for
dehumidification.
1. Remove the cabinet side to gian access to the electrical components.
2. Plug in the unit and turn the humidity control to ON. Check for volts from compressor black wires on
compressor relay to white wire on compressor capacitor using an AC voltmeter.
2.1 If correct voltage is present, go to next step.
2.2 If no voltage, there may be a loose connection in the compressor circuit. Test each component
for continuity. See the appropriate section if a defect is suspected.
3. Unplug the unit and then disconnect the connector from the side of the compressor. Using an
ohmmeter, check continuity between the points listed below.
4. Compressor terminals C and S: No continuity indicates an open start winding. The compressor must
be replaced. Normal start winding resistance is 1 to 2 ohms.
5. Compressor terminals C and R: No continuity indicates an open run winding. The compresor must be
replaced. Normal run winding resistance is 1 to 2 ohms.
6. Compressor terminals S and R: No continuity indicates an open winding. The compressor must be
replaced. Normal winding resistance is 2 to 4 ohms.
7. Any compressor terminal and compressor case: Continuity indicates a grounded motor. The
compressor must be replaced.
8. Disconnect the wires from the run capacitor. The capacitor is shorted and must be replaced if
continuity exists between any terminal and ground.
9. Using capacitor or MFD setting on meter test between both capacitor terminals. Compare reading to
capacitor spec on capacitor.
10. If the above test pass but the compressor does not work, the compressor has an internal mechanical
defect and must be replaced. CONTINUES ON NEXT PAGE.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
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11. Using capacitor or MFD setting on meter test between both capacitor terminals. Compare reading to
capacitor spec on capacitor.
12. If the above test pass but the compressor does not work, the compressor has an internal mechanical
defect and must be replaced.
7.6B REPLACING A BURNT COMPRESSOR
The refrigerant and oil mixture in a compressor is chemically very stable under normal operating conditions.
However, when an electrical short occurs in the compressor motor, the resulting high temperature arc causes
a portion of the refrigerant oil mixture to break down into carbonaceous sludge, a very corrosive acid, and
water. These contaminants must be carefully removed otherwise even small residues will attack replacement
compressor motors and cause failures.
The following procedure is effective only if the system is monitored after replacing the compressor to insure
that the clean up was complete.
1. This procedure assumes that the previously listed compressor motor circuit tests revealed a shorted or
open winding.
2. Remove and properly dispose of the system charge. DO NOT vent the refrigerant or allow it to contact your
eyes or skin.
3. Remove the burned out compressor. Use rubber gloves if there is any possibility of contacting the oil or sludge.
4. To facilitate subsequent steps, determine the type of burn out that occurred. If the discharge line shows no
evidence of sludge and the suction line is also clean or perhaps has some light carbon deposits, the burn out
occurred while the compressor was not rotating. Contaminants are therefore largely confined to the compressor
housing. A single installation of liquid and suction line filter/driers will probably clean up the system.
If sludge is evident in the discharge line, it will likely be found in the suction line. This indicates the compressor
burned out will running. Sludge and acid have been pumped throughout the system. Several changes of the
liquid and suction filter/driers will probably be necessary to cleanse the system.
5. Correct the system fault that caused the burn out. Consult the factory for advice.
6. Install the replacement compressor with a new capacitor and an oversized liquid line filter.
In a running burn out, install an oversized suction line filter/drier between the accumulator and compressor.
Thoroughly flush the accumulator with refrigerant to remove all trapped sludge and to prevent the oil hole
from becoming plugged. A standing burn out does not require a suction line filter/drier.
7. Evacuate the system with a good vacuum pump and accurate vacuum gauge. Leave the pump on the system
for at least an hour.
8. Operate the system for a short period of time, monitoring the suction pressure to determine that the suction
filter is not becoming plugged. Replace the suction filter/drier if pressure drop occurs. If a severe running burn
out has occurred, several filter/driers may have to be replaced to remove all of the acid and moisture.
NOTE: NEVER USE THE COMPRESSOR TO EVACUATE THE SYSTEM OR ANY PART OF IT.
7.6C REPLACING A COMPRESSOR, NON BURN OUT
Remove the refrigerant from the system. Replace the compressor and liquid line filter/drier. Charge the
system to 50 PSIG and check for leaks. Remove the charge and weigh in the refrigerant quantity listed on the
nameplate. Operate the system to verify performance.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
QUESTCLIMATE.COM(877) 420-1330
7.7 REMOTE CONTROLS
The Quest 100 Dehumidifier is controlled by devices mounted on a panel that is remote from the unit. You may
or may not have the devices listed below depending on the model of the remote hygrostat you purchased. If
the Quest 100 Dehumidifier fails to operate as desired, always check the settings of the controls to ensure that
they are correct. Check that the controls are receiving 24VAC from the Quest 100 Dehumidifier. Check the
connections between the Quest 100 Dehumidifier, the hygrostat, and the field control wiring.
7.7A HUMIDITY CONTROL
The humidity control is an adjustable switch that closes when the relative humidity of the air in which it
is located rises to the set point. It opens when the RH drops 4 to 6% below the set point. If the Quest 100
Dehumidifier does not run, try turning the humidity control Down using arrow on control pad. If it then runs, the
humidity control is out of calibration or the RH is below setpoint.
7.8 DEFROST SYSTEM
The Quest 100 Dehumidifier is equipped with an automatic defrost mechanism. If the Quest 100 Dehumidifier
operates in conditions that develop frost on the evaporator, it will sense the frost build-up and automatically
defrost the evaporator. The Quest 100 Dehumidifier may not appear to be operating correctly during the defrost
sequence, but once the defrost sequence is completed, the Quest 100 Dehumidifier will resume dehumidifying.
The evaporator temperature sensor is installed into the center of the evaporator coil. It will automatically
shut the compressor off if the temperature drops due to excessive frost formation on the evaporator coil. The
impeller fan will continue to run, causing air to flow through the evaporator coil and melt the ice. When the ice
has melted, the evaporator temperature will rise, and the control will restart the compressor.
7.9 CONDENSATE PUMP KIT
An optional condensate pump kit is available from the factory for use with the Quest 100 Dehumidifier.
Condensate is automatically pumped to a remote location when the water level in the pump’s reservoir rises to
close the float switch.
The pump also contains a safety float switch. The white leads from this switch extend from beneath the
pump cover. These leads should be extended to the FLOAT terminals on the terminal block and the factory
float jumper removed. If the pump fails, the safety switch opens causing the compressor to stop and water
production to cease before the reservoir overflows. E4 will be displayed on the control panel. The Quest 100
Dehumidifier will not dehumidify until this switch closes.

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QUEST 100 INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
QUESTCLIMATE.COM(877) 420-1330
7.10 POWER CORD REPLACEMENT
WARNING! Servicing the Quest 100 Dehumidifier, with its high pressure refrigerant system
and high voltage circuitry presents a health hazard which could result in death, serious bodily injury,
and/or property damage. Only qualified service people should service this unit.
TOOLS REQUIRED:
• T25 Torx Driver
• 11/32” Driver
Following all local and national electrical codes and standards, route electrical service to the location
that the dehumidifier will be installed.
1. Disconnect power cord from power source.
2. Use T25 Torx driver to remove 6 screws on access panel and remove panel. Modular cable will be
connected to User Interface Assembly. Cable must be carefully unplugged during removal of access
panel.
3. Use T25 Torx driver to remove screw from electrical box cover and remove cover.