Evaporator Is Frozen Up - Hoshizaki KML-351MAH Service Manual

Problem
[8] All components
run, but no ice is
produced.

2. Evaporator is Frozen Up

Problem
[1]Freeze cycle time is
too long.
Possible Cause
a) Refrigerant
b) Compressor
c) Hot Gas Valve
d) Liquid Line Valve
(if applicable)
e) Inlet Water Valve
f) Expansion Valve
g) Headmaster (C.P.R.)
(remote air-cooled
model only)
h) Water Supply Line
(water-cooled model
only)
i) Water Regulating Valve
(water-cooled model
only)
Possible Cause
a) Inlet Water Valve
b) Float Switch
c) Evaporator
d) Spray Tubes
e) Water Pump
f) Thermistor
g) Refrigerant
h) Expansion Valve
i) Control Board
1. Low charge.
2. Air or moisture
trapped.
1. Defective.
1. Continues to open in
freeze cycle.
1. Continues to close in
freeze cycle.
1. Water valve is wide
open during freeze.
1. Bulb loose.
2. Operating erratically.
1. Not operating properly
and liquid line
temperature too warm.
1. Condenser water
pressure too low or
off and high pressure
control opens and
closes frequently.
1. Set too high.
1. Diaphragm does not
close.
1. Float does not move
freely.
2. Defective switch.
1. Scaled up.
2. Damaged.
1. Dirty.
2. Out of position.
1. RPM too slow.
1. Loose or
disconnected.
1. Low charge.
1. Bulb loose.
2. Operating erratically.
1. Defective.
36
Remedy
1. Check for leaks. Recover,
repair, evacuate, and
recharge.
2. Replace drier, evacuate,
and recharge.
1. Replace.
1. Check and replace.
1. Check and replace.
1. Check for water leaks with
icemaker off.
1. Secure bulb.
2. Check and replace.
1. Replace headmaster.
1. Check and get
recommended pressure.
1. Adjust or replace. See
"V.I. Adjustment of Water
Regulating Valve - Water-
Cooled Model Only."
Remedy
1. Check for water leaks with
icemaker off.
1. Clean or replace.
2. Check and replace.
1. Clean.
2. Replace.
1. Clean.
2. Place in position.
1. See chart 1.[5].
1. See "V.J. Removal
and Replacement of
Thermistor."
1. Check for leaks. Recover,
repair, evacuate, and
recharge.
1. Secure bulb.
2. Check and replace.
1. See "II.C.4. Control Board
Check Procedure."