Service Manual

32
2. Freeze-Up
Defrost and clean the icemaker prior to diagnosing freeze-up. Fill out a freeze-up checklist.
The freeze-up checklist can be found in the Hoshizaki Technician's Pocket Guide or contact
your local distributor for a copy of the freeze-up checklist.
Freeze-Up - Possible Cause
Harvest Cycle
1. Evaporator a) Scaled up.
b) Damaged.
2. Cube Guides a) Out of position.
b) Damaged.
3. Spray Tubes and/or Spray
Guides
a) Dirty.
b) Out of position.
4. Water Supply a) Low water pressure.
b) External water lters clogged.
c) Insufficient water line size.
Minimum 3/8" nominal ID copper water tubing or equivalent.
5. Inlet Water Valve a) Defective.
6. Float Switch
See "II.F. Float Switch Check and
Cleaning"
a) Float does not move freely.
b) Defective.
7. Refrigerant Charge a) Low.
8. Control Board
See "III. Controls and
Adjustments" and "II.D. Control
Board Check"
a) Harvest timer (S4 dip switch 1 & 2) set too short.
b) Harvest pump timer (S4 dip switch 7) not in factory default position.
c) Defective.
9. Bin Control
See "II.E. Bin Control Check"
a) Bulb out of position.
b) Defective.
10. Thermistor
See "II.G. Thermistor Check"
a) Loose, disconnected, or defective.
11. Thermostatic Expansion Valve a) Defective.
12. Hot Gas Valves (KMS & SRK) a) Closed or restricted.
13. Liquid Line Valves (KMS & SRK) a) Open.
Freeze Cycle
1. Evaporator a) Scaled up.
b) Damaged.
2. Spray Tubes, Spray Guides, or
Splash Guard
a) Dirty.
b) Out of position.
3. Refrigerant Charge a) Low.
4. Control Board
See "II.D. Control Board Check"
a) Freeze timer (S4 dip switch 9 & 10) set incorrectly.
b) Defective.
5. Inlet Water Valve a) Leaking by.
6. Float Switch
See "II.F. Float Switch Check and
Cleaning"
a) Float does not move freely.
b) Defective.
7. Pump Motor a) RPM too slow.
b) Impeller damaged.