Hoshizaki KM-1301SAH/3 Service Manual page 31

If 115VAC is present on terminal #3 (P) and not on terminal #5 (Y), replace X10 relay.
If 115VAC is present on X10 relay terminal #7 (Y) and PM is not energized, check for
115VAC at X10 relay terminal #4 (R) to neutral (W) and terminal #6 (DBU) to neutral
(W). If 115VAC is present on terminal #6 (DBU) and not on terminal #4 (R), replace X10
relay. If 115VAC is present on X10 relay terminal #4 (R), check control switch contact
continuity between terminals #4 (R) and #5 (R). If contacts are open, replace control
switch. If contacts are closed and 115VAC is present between control switch terminal #5
(R) and neutral (W), check PM capacitor and motor winding continuity.
5c) Initial Harvest Cycle Termination Diagnosis: When the thermistor reaches 48°F
(9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the
harvest timer (S4 dip switch 1 & 2). Check discharge line temperature. For a thermistor
check, see "II.F. Thermistor Check." If 1-min. fill cycle starts after harvest timer
terminates, check that FS is clean and operating properly, see "II.E. Float Switch Check
and Cleaning." If FS is closed, CB proceeds to the next cycle. If not, replace CB.
Note: The minimum total time allowed by CB for a complete harvest cycle is 2 min.
Maximum harvest time allowed is 20 min.
NOTICE! S4 dip switch 7 must remain on. Otherwise, PM will not energize during
the last 50 sec. of harvest.
6) Freeze Cycle – LED 1 is on. Comp, FMR, and PM continue. FM and LLV energize.
HGV and X10 relay de-energize. Appliance is held in freeze by a 5-min. short cycle
protection timer. After 5-min. timer terminates and FS opens, freeze cycle terminates.
Note: PM power supply switches from CB K1 #5 (DBU) in harvest to K1 #4 (R) in freeze.
a) Freeze Cycle Diagnosis: Confirm Comp, FMR, and PM continue. Confirm that
FM and LLV energize. Confirm WRV opens. Next, confirm HGV and X10 relay
de-energize. During the first 5 min. of freeze, confirm evaporator is cooling. If not,
confirm WV de-energized (not leaking by), HGV de-energized (not bypassing), LLV
and FM energize, TXV and HM operate correctly, WRV opens, Comp is efficient, and
refrigerant charge is correct. See "VIII.A. Specification and Performance Data."
b) Comp and FMR Diagnosis: If Comp and FMR de-energize once freeze begins,
check that appliance has not shut off on HPS ("POWER OK" LED off). If so, check
"3)b) HPS Diagnosis" above. If "POWER OK" LED is on, check for 115VAC at CB K1
#1 (V) or #9 (V) to neutral (W). If 115VAC is not present and LED 1 is on, replace CB.
If 115VAC is present, check for 115VAC at CR or MC coil. If 115VAC is present, check
CR or MC coil and contact continuity. Replace as needed. If CR or MC is okay, check
Comp start relay and start and run capacitors. Next, check Comp motor winding
continuity. If Comp is energized but evaporator is not cooling, check for an inefficient
Comp. See "VIII.A. Specification and Performance Data." If Comp is energized but
FMR is not, check for 115VAC at the FMR junction box. If 115VAC is not present,
check icemaker wiring connections. If 115VAC is present, check for voltage at
condenser unit. If 115VAC is not present, check field wiring connections. If 115VAC is
present, check FMR capacitor, motor winding, and fan blade for binding.
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