Freeze-Up - Hoshizaki KM-230BAJ Service Manual

2. Freeze-Up

Defrost and clean the icemaker prior to diagnosing freeze-up. Fill out a freeze-up check
list.
See the Hoshizaki America Technician's Pocket Guide or contact your local distributor
for a copy of the freeze-up checklist.
PROBLEM
[1] Freeze cycle a) Float Switch
time is too
long.
b) Inlet Water Valve
c) Control Board
[2] All ice formed a) Evaporator
on Evaporator
b) Water Supply Line 1. Water pressure too low.
does not fall
into bin in
c) Inlet Water Valve
harvest cycle.
d) Ambient and/or
e) Thermistor
f) Control Board
[3] Others a) Spray Tubes
b) Water System
c) Refrigerant
d) Expansion Valve
e) Hot Gas Solenoid
f) Water Supply Line
g) Water Filter
POSSIBLE CAUSE
1. Leads shorted or defective
2. Float does not move freely.
1. Diaphragm does not close.
1. Defective.
1. Scaled up.
1. Dirty mesh filter or orifice.
2. Diaphragm does not close.
1. Too cool.
water temperature
1. Out of position or loose
1. Harvest timer is set too
2. Defective.
1. Clogged.
2. Out of position.
1. Dirty.
1. Undercharged.
1. Bulb out of position or loose
2. Defective.
1. Coil winding open.
Valve
2. Plunger does not move.
3. Wiring to hot gas valve.
1. Too small; requires minimum
1. Flow rate too small.
switch.
attachment.
short.
attachment.
1/4" nominal ID copper water
tubing or equivalent line
dedicated per machine.
27
REMEDY
1. Check and replace.
2. Clean or replace.
1. Check for water leaks
with icemaker off.
Replace if necessary.
1. See "II.C. Control Board
Check".
1. Clean.
1. Check and get
recommended pressure.
1. Clean.
2. Check for water leaks
with icemaker off.
Replace if necessary.
1. Increase temperature.
1. See "II.F. Thermistor
Check".
1. Adjust longer, referring to
"III.C.2 Harvest Timer".
2. See "II.C. Control Board
Check".
1. Clean.
2. Place in position.
1. Clean.
1. Check for leaks and
recharge.
1. Place in position.
2. Replace.
1. Replace.
2. Replace.
3. Check for loose
connection or open, and
replace.
1. Increase water supply
line size.
1. Replace with filter that
has larger flow rate.