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Quest
DRY
150 Installation, Operation and Maintenance Instructions
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quest
Asset Protection and IAQ Solutions
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FOR HVAC INSTALLER ONLY
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, Nonburn 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.
7.7 Remote Controls
The Quest
DRY
150 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 control panel you purchased.
If the Quest
DRY
150 fails to operate as desired, always check the settings of the controls to insure that they
are correct. Check that the controls are receiving 24Vac from the Quest
DRY
150. Check the connections
between the Quest
DRY
150, the control panel, 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 dial set point. It opens when the RH drops 4 to 6% below the set point. If the Quest
DRY
150 does not run, try turning the humidity control clockwise until it reaches the stop and the knob pointer
points at “Max Dry” (see back of control panel cover). If it still does not run, remove the stop screw from the
panel and turn the knob farther. If it then runs, the humidity control is out of calibration or the RH is below
40%.
The Quest
DRY
150 is equipped with an automatic defrost mechanism. If the Quest
DRY
150 operates in
conditions that develop frost on the evaporator, it will sense the frost build-up and automatically defrost the
evaporator. The Quest
DRY
150 may not appear to be operating correctly during the defrost sequence, but
once the defrost sequence is completed, the Quest
DRY
150 will resume dehumidifying.
7.7B Programmable Ventilation Timer
The ventilation timer controls the impeller fan and the motorized fresh air damper. When the ventilation
timer is activated, the Quest
DRY
150 will circulate the indoor air, and bring in fresh air from outside.
The ventilation timer should be set for the required ventilation of the residence. The structure should be
ventilated with fresh air as suggested by applicable codes and standards.
If the Quest
DRY
150 fails to ventilate as expected, check that the time on the timer is correct. For the timer
to carry out the program schedule, the slide switch in the upper left corner on the timer must be set to
“AUTO”
. The slide switch in the upper right corner of the Quest
DRY
150 must be set to
“RUN”
. Also check
the programs on the timer to be sure that the timer is calling for ventilation at the correct times. If the timer
fails to operate or operates erratically, reset the timer; see section 4.5 of this manual.
FOR HVAC INSTALLER ONLY
