Service Diagnosis - Hoshizaki KM-230BAJ Service Manual

B. Service Diagnosis
• The appliance should be diagnosed and repaired only by qualified service
personnel to reduce the risk of death, electric shock, serious injury, or fire.
• Risk of electric shock. Control switch in "OFF" position does not de-energize all
loads. Use extereme caution and exercise safe electrical practices.
• Moving parts (e.g., fan blade) can crush and cut. Keep hands clear.
• Before servicing the appliance, move the control switch to the "OFF" position and
unplug the appliance.
• CHOKING HAZARD: Ensure all components, fasteners, and thumbscrews are
securely in place after the appliance is serviced. Make sure that none have fallen
into the ice storage bin.
• Make sure all food zones in the appliance and ice storage bin are clean after
service.
The diagnostic procedure is basically a sequence check which can be used at unit start-
up or for system diagnosis. Using this check out procedure will allow you to diagnose
electrical system and component failures in approximately 10 minutes under normal
operating conditions of 70°F (21°C) or warmer air and 50°F (10°C) or warmer water
temperatures. Before conducting a 10 minute checkout, check for correct installation,
proper voltage per unit nameplate and adequate water supply. As you go through the
procedure, check to assure the components energize and de-energize correctly. If not,
those components and controls are suspect.
1) Remove the louver. Move the control switch to the "OFF" position, then unplug the
appliance. Access the control box. Clear any ice from the bin control actuator located
in the bin.
2) Plug in the appliance, then place the control switch in the "ICE" position. A 5 second
delay occurs. The "POWER OK" LED on the control board comes on. If the "POWER
OK" LED is flashing (indicating a full bin), check the bin control. See "II. D. 1 Bin
Control Check".
3) One Minute Fill Cycle – The inlet water valve is energized. After 1 minute, the control
board checks the float switch. If the float switch is closed, the unit cycles to harvest.
If closed, continue to step 4. If the float switch is open, the unit repeats the 1 minute
fill cycle until water enters and the float switch closes (low water safety protection
during initial start up and at the end of each harvest). Diagnosis: If the water valve
does not open, check for no supply voltage at water valve terminals, bad coil, or
plugged screen or external filter (no water flow). If unit fails to start harvest, check for
open float switch or bad 1 minute timer in board.
WARNING
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