Whirlpool 4.3 CU FT Service Manual page 34

COMPONENT TESTING
5. Test the compressor run capacitor.
a. Discharge the capacitor by touching the leads of a
20,000 Ω resistor to the two terminals.
b. Disconnect the wires from the capacitor terminals.
c. ANALOG METER - Set your meter to ohms (resistance)
function, range to R x 10,000, or the highest scale on
the meter. Touch the meter leads to the capacitor
terminals. The meter should indicate nearly a short
circuit initially, then a steady increase in resistance
should be noted. The needle will move more slowly
as it creeps up. If your capacitor has a resistance of at
least 100K (100,000 ohms) it is good.
If the needle doesn't move when you connect the
leads to the capacitor, the capacitor is open. If the
needle indicates a short initially and stays there, the
capacitor is shorted. Replace the capacitor.
DIGITAL METER - If you have a digital multi-meter with
an autoranging function, set the meter to the ohms
(resistance) function. Pay attention to the resistance
units displayed on the meter readout. No units = ohms.
"K" = the readout value times 1,000 ohms. "M" = the
readout value times 1,000,000 ohms.
Proceed as described with the analog meter for the
test. What you're looking for is a low initial resistance
which climbs steadily until it exceeds 100,000 ohms.
If the value is below 100,000 ohms (100K) but above
10,000 ohms (10K), the capacitor is weak and should
be replaced.
6. If the preceding steps did not correct the compressor
problem, proceed to the next section, "Compressor does
not run".
Compressor does not run:
ü Quick Check: Perform 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, left side panel, and console to access
the machine electronics.
3. Check compressor wiring—use an ohmmeter to measure
the resistance at the wire terminal on the compressor
relay (K5) and L2 at the terminal block.
¾ If the resistance is 2–15 Ω, go to step 10.
¾ If an open circuit is detected, go to step 4.
4. Remove the belt and drum to access the compressor/heat
pump assembly.
5. Visually check the connections between the compressor
relay and the compressor components, and the
compressor components and the L2 terminal.
6. If the connections look good, check for continuity between
the wire terminal on the compressor relay (K3) and
terminal "C" (common) on the compressor.
¾ If there is continuity, go to step 8.
¾ If there is no continuity, go to step 7.
7. Remove the compressor cover and check for continuity
across the thermo-switch on the compressor.
¾ If there is continuity, go to step 8.
n
3-10 Whirlpool Compact Heat Pump Dryer
For Service Technician Use Only
¾ If there is no continuity, replace the thermo-switch.
8. Remove the compressor cover and remove all three
motor wires: Common (C)=Black, Run (R)=Red, and Start
(S)=Yellow.
9. Using the following chart, check the resistance values of
the compressor Run and Start winding coils.
NOTE: Run and Start winding coils must be checked at the
compressor.
Winding Resistance in
ohms
RUN 8.03 ± 10%
START 8.89 ± 10%
START & RUN 16.92 ± 10%
¾ If the resistance at the compressor is correct, go to step
10.
¾ If the Run or Start winding resistance is much greater
or less than the values listed in the chart, replace the
heat pump base assembly.
R
Figure 2 - Compressor Diagram
10. If the preceding steps did not correct the problem and
L1 and L2 were both detected during the Quick Check,
replace the ACU.
11. Reassemble all parts and panels.
12. Plug in dryer or reconnect power.
13. Perform the Service Test Cycle on pages 3 and 4 to verify
repair.
Contact Points of
Measurements
Compressor terminal
"C" to terminal "R"
Compressor terminal
"C" to terminal "S"
Compressor terminal
"R" to terminal "S"
S
C
Thermal