quest
quest
1-800-533-7533
Quest
DRY
70
Installation, Operation and Maintenance Instructions
16
www.QuestProtect.com
sales@QuestProtect.com
10. Service
CAUTION
CAUTION: Servicing the Quest Dry 70 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. Please
contact your HVAC professional.
10.1 Technical Description
The Quest Dry 70 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 (See Figure 1). 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 strainer and capillary tubing 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 mixture of gas and liquid refrigerant enter the
accumulator after leaving the evaporator coil. The
accumulator prevents any liquid refrigerant from
reaching the compressor. The compressor evacuates
the cool refrigerant gas from the accumulator and
compresses it to a high pressure and temperature.
10.2 Troubleshooting
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. Defective Compressor relay.
5. Defective control transformer.
Compressor is not running. Dehumidification is being called for. No fan call.
1. Defective compressor run capacitor.
2. Loose connection in compressor circuit.
3. Defective compressor overload.
4. Defective compressor.
5. Defrost thermostat open.
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. Defective compressor overload (Sec. 7.6A).
3. Defective compressor (Sec. 7.6).
4. Defrost thermostat defective (Sec. 7.8).
5. Dirty air filter(s) or air flow restricted.
Refrigeration System of Quest Dry 70
FOR HVAC INSTALLER ONLY
