Manitowoc STH042 4/16, Technician'S Handbook

Page: 57 / 146

Part Number STH042 4/16 57
Problem Checklist
Problem Possible Cause Correction
Ice machine does
not operate
No electrical power to
the ice machine.
Replace the fuse/reset the
breaker/turn on the main
switch/plug power cord
into receptacle.
Ice machine needs to
be turned on.
Press the On/Off button to
start ice making.
Damper in open
position (down).
Damper must be in upright
position and capable of
swinging freely.
Ice machine
stops, and can
be restarted by
turning the ice
machine OFF/ON.
Safety limit feature
stopping the ice
machine..
Refer to “Safety Limit
Feature”
Ice sheet is thick
Water trough level is
too high.
Adjust ice thickness float.
Power button was
turned off/on during
freeze cycle and
ice remained on
evaporator.
Allow ice to thaw and
release from evaporator,
then restart
Ice damper was
opened then closed
in the harvest cycle
before the ice released.
Allow ice to thaw and
release from evaporator,
then restart
Ice machine does
not release ice or is
slow to harvest.
Ice machine is dirty. Clean and sanitize the ice
machine
Ice machine is not
level.
Level the ice machine
Low air temperature
around ice machine
(air-cooled models).
Air temperature must be at
least 40° F (4°C).
Ice machine does
not release ice or is
slow to harvest.
Water regulating valve
leaks in harvest mode
(water-cooled models).
Replace water regulating
valve
Ice machine does
not cycle into
harvest mode.
The six-minute freeze
time lock-in has not
expired yet.
Wait for freeze lock-in to
expire.
Harvest float switch
is dirty.
Clean and sanitize the ice
machine.
Harvest float switch
wire is disconnected.
Connect the wire
Harvest float switch is
out of adjustment.
Adjust the harvest float
switch.
Uneven ice fill (thin at
top of evaporator).
Refer to “Shallow or
Incomplete Cubes”
Troubleshooting