Hoshizaki KMD-700MAH, Service Manual

Page: 55 / 80

55
2. Evaporator is Frozen Up
Problem Possible Cause Remedy
[1] a) Float Switch 1. Leads short-circuit or
defective switch.
1. Check and replace.
2. Float does not move
freely.
2. Clean or replace.
b) Water Solenoid Valve 1. Diaphragm does not close. 1. Check for water leaks with
icemaker off.
c) Controller Board 1. Defective. 1. See "II.2[e] Checking the
Controller Board."
[2] a) Evaporator 1. Scaled up. 1. Clean.
b) Water Supply Line 1. Water pressure too low. 1. Check and get
recommended pressure.
c) Water Solenoid Valve 1. Dirty mesh filter or orifice. 1. Clean.
2. Diaphragm does not close. 2. Check for water leaks with
icemaker off.
d) Ambient and/or water
temperature.
1. Too cool. 1. Increase temperature.
e) Line Valve 1. Continues to open in
harvest cycle.
1. Check operation in harvest
cycle and replace.
f) Thermistor 1. Out of position or loose
attachment.
1. See "V.11. Removal and
Replacement of
Thermistor."
g) Controller Board 1. Defrost timer is set too
short.
1. Adjust longer, referring to
"II.2.[d] Controls and
Adjustments, 2) Defrost
Timer."
2. Defective. 2. See "II.2[e] Checking the
Controller Board."
[3] Other a) Spray Tubes 1. Clogged. 1. Clean
2. Out of position. 2. Place in position.
b) Water System 1. Dirty. 1. Clean.
c) Refrigerant 1. Undercharged. 1. Check for leaks and
recharge.
d) Expansion Valve 1. Bulb out of position or
loose attachment.
1. Place in position.
2. Defective. 2. Replace.
e) 1. Coil winding opened. 1. Replace.
2. Plunger does not move. 2. Replace.
3. Wiring to hot gas valve. 3. Check for loose
connection or open, and
replace.
Freeze cycle time is
too long.
Hot Gas Solenoid
Valve
All ice formed on
evaporator does not
fall into bin in harvest
cycle.
Problem Possible Cause Remedy
[7] Continued from
previous page.
e) Water Supply Line
[Water-cooled model
only]
1. Condenser water pressure
too low or off and pressure
control opens and closes
frequently.
1. Check and get
recommended pressure.