Hoshizaki KML-325MWJ 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 missing or loose jumper (4A4883G01)),
check that the jumper is securely in place. Move ice away from TBC bulb. 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,
confirm jumper (4A5883G01) is in place on CB K4 red connector.
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) wire to neutral (W) then HPS (BK) wire to neutral (W). If 115VAC is present
at HPS (P) wire and not at HPS (BK) wire, HPS is open. See HPS Diagnosis below.
If 115VAC is present at HPS (BK) wire, check for 10.5VAC at CB K2 #1 red (R) wire
to CB K2 #2 red (R) wire. If 10.5VAC is not present, check CT continuity. If open,
replace CT.
b) HPS Diagnosis: Let refrigeration circuit pressures equalize. If HPS does not
reset and pressures are equalized, replace HPS. Check that the condenser coil is
not clogged or restricted. 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.
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 through additional 1-min. fill cycles until water enters the
water tank and 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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