Hoshizaki KMD-460MAJ Service Manual page 19

6) Freeze Cycle – LED 1 is on. Comp, PM, and X14 relay continue. FMR, FM, and LLV
energize. HGV, X10, and X12 relays de-energize. Appliance is held in freeze by a 5-min.
short cycle protection timer. After 5-min. short cycle protection 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.
Slush Control: When slush control is enabled (S5 dip switch 5 "ON"), PM de-energizes
when thermistor reaches 36°F (2.2°C) (5.8kΩ) for 10 sec. then, energizes for the
remainder of the freeze cycle.
a) Freeze Cycle Diagnosis: Confirm Comp, PM, and X14 relay continue. Confirm
that FMR, FM, and LLV energize. Confirm WRV opens. Next, confirm HGV, X10,
and X12 relays 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), FM, FMR, and LLV energize, TXV and HM operate correctly, WRV
opens, Comp is efficient, and refrigerant charge is correct. See "VIII.A. Specification
and Performance Data Sheets."
b) Comp and FMR Diagnosis: If Comp de-energizes once freeze begins, check that
appliance has not shut off on HPS ("POWER OK" LED off). If so, check "3)b) HPS
Diagnosis." 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.
Comp: If 115VAC is present, check for 115VAC at CR coil. If 115VAC is present,
check CR coil and contact continuity. Replace as needed. If CR 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 Sheets."
FMR: 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.
c) WV and HGV Diagnosis: If WV is energized, check for 115VAC at CB K1 #6 (O)
to neutral (W). If 115VAC is present after PM energizes in harvest cycle, replace
CB. If 115VAC is not present, replace WV (bypassing). If HGV did not de-energize
at the end of harvest, check for 115VAC at CB K1 #2 (P) to neutral (W). If 115VAC
is present and LED 3 is off, replace CB. If 115VAC is not present, replace HGV
(bypassing).
d) PM Diagnosis: Confirm water is flowing over evaporator from PM and not WV.
If PM de-energizes once freeze begins, check for 115VAC at CB K1 #4 (R) to
neutral (W). If 115VAC is not present, replace CB. If 115VAC is present and PM is
de-energized, check for 115VAC at control switch #6 (R) to neutral (W) and control
switch #5 (Y) to neutral (W). If 115VAC is present at control switch #6 (R) and not at
control switch #5 (Y), check control switch continuity. Replace as needed. If 115VAC
is present at control switch #5 (Y) to neutral (W), check PM capacitor and motor
winding continuity.
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