COMPONENT TESTING
Whirlpool Compact Heat Pump Dryer
n
3-9
For Service Technician Use Only
DANGER
Electrical Shock Hazard
Only authorized technicians should perform
diagnostic voltage measurements.
After performing voltage measurements,
disconnect power before servicing.
Failure to follow these instructions can result in
death or electrical shock.
TEST #4: Heating System (Compressor)
This test is performed when either of the following situations
occurs:
ü
Heat pump does not heat—Process air flow
ü
Heat pump does not heat—Compressor
ü
Compressor does not start/humming noise
This test checks the components making up the heating circuit.
The following items are part of this system:
Part of Heater System
Heat Pump Dryer
Harness/connection
ü
Compressor relay
ü
Heat pump assembly
ü
Compressor thermistor
ü
Appliance Control Unit (ACU)
ü
TEST #4a: Heat Pump (HE)
IMPORTANT:
The heat pump must be replaced as an assembly
if any of the sealed system components malfunction. This
includes the compressor, heat exchanger components
(evaporator and condenser), the post condenser, expansion
valve, and all tubings and fittings.
Heat pump does not heat—Process air flow:
1. Check both filters (primary lint filter and service filter) for
restriction and clean as necessary.
2. If a significant amount of lint or debris is observed on
the filter, remove the exchanger cover and vacuum the
filter and any lint or debris from the fins and coils of the
evaporator and condenser.
Heat pump does not heat—Compressor:
Compressor runs but cycles due to overheating
1. Check for restricted air flow caused by dirty filters or heat
exchanger (see “Process air flow” above).
2. Auxiliary Fan – used to cool the post condenser and
compressor electronics. Perform TEST #10: Auxiliary Fan,
page 21, to verify the operation of the auxiliary (post
condenser) fan.
Compressor does not start/humming noise:
ü
Quick Check:
Perform TEST #1: ACU Power Check, page
12, and the Service Test Cycle on pages 3 and 4 to test for
L1 and L2 line voltage.
¾
If L1 and L2 are present, go to step 1.
¾
If L1 and L2 are not present, go to TEST #2: Supply
Connections, page 13.
1. Unplug dryer or disconnect power.
2. Remove top panel and right side panel to access the
compressor/heat pump assembly.
3. Visually check the connections between the compressor
and run capacitor.
4. If the connections look good, check the capacitor for
leaks, corrosion, bulging of the metal canister, or any
other physical signs that the capacitor should be replaced.
HEAT PUMP (COMPRESSOR) STRIP CIRCUIT
L1
RELAY K3
COMPRESSOR
J5-2
BK
R
J13-1
BK
BR
BR
COMPRESSOR
R
L2
R
S
C
RUN
START
THERMAL
LIMIT
BK
BR
BU
BR
17uF CAP
GND
R
ACU
G-Y
RELAY K5
J13-2
J5-1
ACU
R
8.03 ohms
8.89 ohms
RFI-2
RFI-1
Figure 1 - Compressor Strip Circuit
