KM-650MAH-E Service manual - Hoshizaki

F. Diagnostic Charts
1. No Ice Production
No Ice Production - Possible Cause
1. Power Supply a) Off, blown fuse, or tripped breaker.
b) Not within specifications.
2. Fuse (Power Cord) a) Blown.
3. Main Transformer
a) Coil winding open or shorted.
(230VAC/115VAC)
4. Fuse (Control Box) a) Blown.
5. Thermostatic Bin Control a) Tripped with bin filled with ice.
(KM-320MAH-E and
b) Ambient temperature too cool.
KM‐650MAH-E
c) Set too warm.
Aux. Code U-0 and Earlier;
KM-515MAH-E
d) Bulb out of position.
Aux. Code U-1 and Earlier) e) Open contacts, defective.
See "IV.C. Bin Control Check"
6. Control Switch a) In "OFF" or "WASH" position.
b) Bad contacts.
7. High-Pressure Switch a) Dirty condenser.
b) Fan motor not operating.
c) Refrigerant overcharged.
d) Bad contacts.
e) Refrigerant lines or components plugged.
8. Control Transformer
a) Coil winding open or shorted.
(115VAC/10.5VAC)
9. Control Board
a) In alarm.
See "IV.B. Control Board Check" b) Yellow "BC OPEN" LED on (bin full).
c) Defective.
10. Mechanical Bin Control a) Tripped with bin filled with ice.
(KM-320MAH-E and
b) Actuator does not move freely.
KM‐650MAH-E
c) Defective.
Aux. Code U-1 and Later;
KM-515MAH-E
Aux. Code U-2 and Later)
See "IV.C. Bin Control Check"
11. Water Supply a) Water supply off or improper water pressure.
b) External water filters clogged.
12. Inlet Water Valve a) Screen or orifice clogged.
b) Coil winding open.
c) Water valve open in freeze cycle.
13. Float Switch
a) Float does not move freely.
See "IV.D. Float Switch Check b) Defective.
and Cleaning"
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