Service Manual

Table Of Contents
17
1. "G" Control Board without Harvest Pump Timer Operation 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.1. Thermostatic Bin Control (TBC) Check."
NOTICE! Do not adjust S4 dip switch 7 out of the factory default position. This dip
switch must be left in the factory default position or the appliance will not operate
correctly.
Note: CB red "POWER" LED remains on unless the 10.5VAC power supply is
interrupted (K2 connector).
a) Power On Diagnosis: If CB red "POWER OK" LED is off, conrm 10A fuse is good.
Check for 115VAC at control switch #2(BR) to neutral (W) then at control switch
#3(P) to neutral (W). If 115VAC is present on #2 (BR) 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 (R) to CB K2 #2 (R). 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 tting. On water-cooled models, conrm WRV opens in freeze
cycle.
Conrm that the location meets installation requirements:
The appliance is not intended for outdoor use. Normal operating ambient temperature
should be within 45°F to 100°F (7°C to 38°C).
Allow 6" (15 cm) clearance at rear, sides, and top for proper air circulation and ease of
maintenance and/or service should they be required.
The appliance should not be located in a corrosive environment.