Section 6
Service
6-3
Component Specifications and Diagnostics
WARNING
An ice machine contains high voltage electricity and refrigerant charge. Repairs are to be performed by
properly trained refrigeration technicians aware of the dangers of dealing with high voltage electricity and
refrigerant under pressure.
MAIN FUSE
Function
The control board fuse stops ice machine operation
if electrical components fail causing high amp draw.
Specifications
The main fuse is 250 Volt, 8 amp.
Check Procedure
WARNING
High (line) voltage is applied to the control board
(terminals #8 and #2) at all times. Removing the
control board fuse or moving the toggle switch to
OFF will not remove the power supplied to the
control board.
1.
Verify power is supplied to the ice machine. If
the control board light is on the fuse is good.
WARNING
Disconnect electrical power to the entire ice
machine before proceeding.
2.
Remove the fuse. Check the resistance across
the fuse with an ohm meter.
Reading
Result
Open (OL)
Replace fuse
Closed (O)
Fuse is good
CONTROL BOARD RELAYS
Function
The control board relays energize and de-energize
system components.
Specifications
Relays are not field replaceable. There are three
relays on the control board:
Relay
Controls
#1
Compressor
#2
Water Inlet Valve/Hot Gas Valve
#3
Condenser Fan Motor/Water Pump
ON/OFF/WASH TOGGLE SWITCH
Function
The switch is used to place the ice machine in ON,
OFF or WASH mode of operation.
Specifications
Single-pole, Single-throw switch (SPST). The
switch is connected into a varying low D.C. voltage
circuit.
Check Procedure
NOTE: Because of a wide variation in D.C. voltage,
it is not recommended that a voltmeter be used to
check toggle switch operation.
1.
Inspect the toggle switch for correct wiring.
2.
Isolate the toggle switch by disconnecting all
wires from the switch, or by disconnecting the
molex connector from the control board.
3.
Check across the toggle switch terminals using a
calibrated ohmmeter. Note where the wire
numbers are connected to the switch terminals,
or refer to the wiring diagram to take proper
readings.
Switch Setting
Terminals
Ohm Reading
7-4
Open
ON
7-12
Closed
12-4
Open
7-12
Open
WASH
7-4
Closed
12-4
Open
7-12
Open
OFF
7-4
Open
12-4
Open
Replace the toggle switch if ohm readings do not
match all three-switch settings.
