Technical Description; Troubleshooting - Honeywell Home DR90A3000 Guía De Instalación Profesional

Technical Description

DR90A3000/DR120A3000 uses a refrigeration system
similar to an air conditioner 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 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.

Troubleshooting

Troubleshooting videos are available on the Resideo Pro YouTube channel playlist.
CAUTION: Servicing the DR65A3000 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. Service should only be performed by a qualified service technician.
Problem
No dehumidification. Neither
fan nor compressor run and the
ventilation timer is OFF.
No dehumidification. Compressor
does not run but fan runs when
there is a call for dehumidification
and the ventilation control is OFF.
Fan runs when there is a call
for dehumidification and the
ventilation control is OFF, but the
compressor cycles on and off too
frequently.
12
STRAINER/FILTER
Recommended Troubleshooting Steps
1. Unit unplugged or no power to outlet.
2. Humidity control set too high or defective.
3. Loose connection in internal or control wiring.
4. Defective compressor relay.
5. Defective control transformer.
6. Optional Condensate Pump Safety Switch open.
1. Defective compressor run capacitor.
2. Bad connection in compressor circuit.
3. Defective compressor overload.
4. Defective compressor.
5. Defrost thermostat open.
6. Optional Condensate Pump Safety Switch open.
1. Low ambient temperature and/or humidity causing unit to cycle
through defrost mode.
2. Defective compressor overload.
3. Defective compressor.
4. Defrost thermostat defective.
5. Dirty air filter(s) or airflow restricted.
6. Low refrigerant charge, causing defrost control to cycle.
7. Bad connection in compressor circuit. Fan does not run with
fan switch in either position.
DR90A3000/DR120A3000 Dehumidification System 33-00298EFS—09
DRIER
CONDENSER
EVAPORATOR
COMPRESSOR
CAPILLARY
TUBES
ACCUMULATOR
M27404