Hoshizaki KMD-460MAJ Service Manual page 16

1. Diagnosis
3) Power On: Turn on the power supply, then move the control switch to the "ICE" position.
A 5-sec. delay occurs. CB red "POWER OK" LED and green "BC CLOSED" LED turn
on. If yellow "BC OPEN" LED is on (indicating a full bin), check BC. Move ice away from
BC actuator paddle. If yellow "BC OPEN" LED stays on, see "II.D. Bin Control Check.".
Note: • CB red "POWER OK" LED remains on unless the 10.5VAC power supply is
interrupted (K2 connector).
• Check CB using the steps in "II.C. Control Board Check."
• Confirm CB green "BC CLOSED" LED is on. If CB yellow "BC OPEN" LED is on,
remove ice from BC. If no ice is around BC and yellow "BC OPEN" LED is on,
see "II.D. Bin Control Check."
a) Power On Diagnosis: If CB red "POWER OK" LED is off, confirm 10A fuse is good.
Check for 115VAC at control switch #2 (BK) to neutral (W) then at control switch
#3 (P) to neutral (W). If 115VAC is present on #2 (BK) and not on #3 (P), replace
control switch. If 115VAC is present on control switch #3 (P), check for 115VAC at
HPS (P) to neutral (W) then HPS (BK) to neutral (W). If 115VAC is present at HPS
(P) and not at HPS (BK), HPS is open. See HPS Diagnosis below. If 115VAC is
present at HPS (BK), check for 10.5VAC at CB K2 #1 red wire to CB K2 #2 red wire.
If 10.5VAC is not present, check CT continuity. If open, replace CT.
b) HPS Diagnosis: Check that the condenser coil is not clogged or restricted. Let
refrigeration circuit pressures equalize. If HPS does not reset and pressures are
equalized, replace HPS. If pressures are not equalized, reclaim refrigerant and
diagnose refrigeration circuit restriction. Check that there are no restrictions in the
refrigeration circuit.
Harvest Cycle: HGV, strainer, or check valve.
Freeze Cycle: FM, FMR, TXV, WRV, HM, LLV, strainer, check valve, drier, and
damaged line set or fitting. On water-cooled models, confirm WRV opens in freeze
cycle.
Confirm that the location meets installation requirements. See the appliance's
instruction manual for details.
4) 1-Min. Fill Cycle – LED 4 is on. WV and X11 relay energize. Water begins to fill the
water tank. After 1 min., CB checks for a closed FS. If FS is closed, the harvest cycle
begins (X10, X12, X14, Comp, HGV, and FMR energize), Continue to step 5a. If FS is
open, WV remains energized until FS closes (low water safety protection during initial
start up and at the end of each harvest).
Diagnosis: Check that water enters the water tank. If not, check that the water supply
line shut-off valve is open and screens or external filters are clear. Check for 115VAC
at CB K1 #6 (O) to neutral (W). If 115VAC is not present, replace CB. If 115VAC is
present, and WV does not energize, check for 115VAC at WV. If 115VAC is present,
check coil continuity. If open, replace WV. If the water tank fills, but the appliance fails to
start harvest (Comp energized), check for open FS. See "II.E. Float Switch Check and
Cleaning." If FS is closed and CB fails to start the harvest cycle after 1 min., replace
CB.
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