Publicidad
Idiomas disponibles
Idiomas disponibles
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.
Defrost
If the DR90 or DR120 dehumidifier coil starts to freeze up it goes into defrost mode. The dehumidifier shuts
off the compressor and runs the fan until the coil temperature rises. For rev 2 models (a sideways 2 after the
model number on the sticker) the dehumidifier makes a single beep when first powered up or when it enters
defrost mode.
Troubleshooting
CAUTION: Servicing the DR90A3000/DR120A3000 with its high pressure refrigerant system and
Troubleshooting videos are available on the Resideo Pro YouTube channel playlist.
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
Neither the
dehumidifier fan
nor compressor
run when
the control
is calling for
dehumidification.
The dehumidifier
fan runs but the
compressor does
not when the con-
trol is calling for
dehumidification.
12
Troubleshooting Steps/Possible Causes of Issue
1. Verify the drain line is not clogged. An internal float switch can lock out the
dehumidifier if the drain line gets clogged.
2. Wait 5 minutes from the time you made the call for dehumidity. Series 2 versions
of the DR90 and DR120 have a 2-5 minute compressor protection delay. If the
control is digital, it may also have a delay. These delays will overlap, so if the
humidity control has been calling for over 5 minutes and power has not cycled, the
dehumidifier should run.
3. If it does not run after the delay, install a jumper between the R and DHUM
terminals on the dehumidifier. This bypasses the control circuit. If the unit runs,
the issue was with the control or wires to the control.
4. If the unit still does not run within 5 minutes of installing a jumper from R to
DEHUM, verify voltage to the outlet that the dehumidifier is plugged into. This
should be 120 VAC nominal and if it drops below 102 VAC or above 132 VAC, the
dehumidifier will not run.
If there is a wire to "FAN" on the dehumidifier, remove that wire and see if the dehu-
midifier fan continues to run. If the fan shuts off, then whatever is controlling the
fan was calling for ventilation. That doesn't mean a control is calling for dehumidity.
Follow the steps from the first issue for further testing.
If there is no wire to the "FAN" terminal and the dehumidifier FAN is running but the
compressor is not, the dehumidifier may be running in defrost.
STRAINER/FILTER
DRIER
CONDENSER
EVAPORATOR
DR90A3000/DR120A3000 Dehumidification System 33-00298EFS—15
COMPRESSOR
CAPILLARY
TUBES
ACCUMULATOR
M27404
Publicidad
