Hoshizaki KM-81BAJ Service Manual page 20

Pump-Out Diagnosis: In the freeze cycle before pump-out (see table above), after
thermistor reaches 36°F (2°C) and the 5 min. short cycle protection timer has
terminated, disconnect the FS connector. Check that CB LEDs 4, 5, 6, and 7 are on, PM
stops, then restarts, DV energizes, and water is flowing down the drain through DV. If not,
continue to steps below.
a) CB Diagnosis: Confirm FM de-energizes. If FM is energized with LEDs 4, 5, 6, and
7 on, replace CB. If PM does not stop and restart and DV does not energize, check
that CB LEDs 4, 5, 6, and 7 are on. If not, replace CB. If LEDs 4, 5, 6, and 7 are
on and PM is not energized, check for 115VAC at CB K5 #3 (DBU) to neutral (W).
If 115VAC is not present, replace CB. If 115VAC is present at CB K5 #3 (DBU) and
PM is not energized, continue to "b) PM Diagnosis:" below. If PM is energized and
DV is not energized, check for 115VAC at CB K5 #6 (GY) to neutral (W). If LED 4 is
on and 115VAC is not present at CB K5 #6 (GY), replace CB.
b) PM Diagnosis: Confirm water is flowing down DV. If not check for 115VAC CB K5 #3
(DBU) to neutral (W). If 115VAC is not present, replace CB. If 115VAC is present and
PM is de-energized, check PM capacitor, motor winding, wiring connections, and
impeller for binding.
c) DV Diagnosis: Confirm water is flowing down DV. If not check for 115VAC at CB K5
#6 (GY) to neutral (W). If 115VAC is not present, see "b) CB Diagnosis:" above.
If 115VAC is present at CB K5 #6 (GY) and DV is de-energized, check DV coil
continuity, make sure the drain line is not clogged and that DV is clean and operating
properly.
8) Normal Harvest Cycle – Same as the initial harvest cycle. Return to step 5a) above.
Note: Appliance continues to cycle until BC is satisfied or power is switched off. The
appliance always restarts at the 1-min. fill cycle.
2. Shutdown Diagnosis
1) See "II.D.1. Bin Control Check."
Legend: BC–bin control; CB–control board; Comp–compressor; CR–compressor relay;
DV–drain valve; FM–fan motor; FS–float switch; HGV–hot gas valve;
HPS–high-pressure switch; PM–pump motor; TXV–thermostatic expansion valve;
WRV–water regulating Valve; WV–inlet water valve
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