Service Manual
Table Of Contents
- Important Safety Information
- I. Construction and Water/Refrigeration Circuit Diagram
- II. Sequence of Operation and Service Diagnosis
- III. Controls and Adjustments
- A. Control Board Layout
- B. LED Lights and Audible Alarm Safeties
- C. Settings and Adjustments
- 1. Default Dip Switch Settings
- 2. Harvest Timer (S4 dip switch 1 & 2)
- 3. Pump-Out Timer (S4 dip switch 3 & 4)
- 4. Pump-Out Frequency Control (S4 dip switch 5 & 6)
- 5. Harvest Pump Timer Operation (S4 dip switch 7)
- 6. Factory Use (S4 dip switch 8)
- 7. Freeze Timer (S4 dip switch 9 & 10)
- 8. Float Switch Selector (S5 dip switch 1)
- 9. Refill Counter (S5 dip switch 2, 3, and 5), Program Selector (4)
- D. Switches
- IV. Refrigeration Circuit and Component Service Information
- V. Maintenance
- VI. Preparing the Appliance for Periods of Non-Use
- VII. Disposal
- VIII. Technical Information
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2. "G" Control Board with 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 full bin):
KML-351MAH, KML-631M_H: 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."
KMD-460M_H, KMD-530M_H: Check MBC. Move ice away from MBC actuator paddle.
If yellow "BC OPEN" LED stays on, see"II.D.2. Mechanical Bin Control (MBC) Check
and Cleaning."
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 OK" 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, conrm 10A fuse is good.
Check for 115VAC at control switch #2 (BR or BK) to neutral(W) then at control
switch #3(P) to neutral (W). If 115VAC is present on #2 (BR or 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). If115VAC is present
at HPS (P) and not at HPS (BK), HPS is open. See HPS Diagnosis below. If115VAC
is present at HPS (BK), check for 10.5VAC at CB K2#1 (R) to CB K2#2(R).
If10.5VAC 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, conrm WRV opens in freeze
cycle.
Conrm 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. KMD-460/530MAH require
12"(30cm) clearance at right side.
• The appliance should not be located in a corrosive environment.