Test Procedures - Loads - Scotsman C2648 - SERVICE MANUAL 11-2010 Service Manual

C2648 Service Manual

Test Procedures - Loads

Harvest assist solenoid
1. Test using the controller's indicator lights. Push and release the Harvest button. The Hot Gas indicator
light will be on. At the same time the Harvest Assist Solenoid will be powered. If the ice on the
evaporator is thin, the solenoid will extend. If the ice is nearly full sized, the solenoid will press against
the ice until it releases from the evaporator, then the solenoid probe will extend. If the probe extends, the
solenoid is good. If not, do a voltage check. Unplug the high voltage harness from the harvest assist
solenoid. Attach a voltmeter to the harness connector. Push and release the Harvest button. There
should be full voltage at the connector. If there is and the solenoid does not extend, replace the solenoid.
If full voltage is not present, check voltage at the controller. If there is no voltage, check voltage from the
controller. The hot gas / harvest assist pin is 5.
Note: The coil of this valve is internally rectified, will normally show infinite resistance when tested with
an ohmmeter.
Hot Gas or Vapor Valve
1. Test using the controller's indicator lights. If the unit is running, or has been off for more than 4
minutes, push and release the Harvest button. The Hot Gas indicator light will be on and the hot gas
valves will be energized. The compressor will force discharge gas into the evaporator inlet, warming it. If
the evaporator inlet does not warm up, do a voltage check. Shut the unit off by holding the Off button in
for 3 seconds. Unplug the high voltage harness from the hot gas solenoid. Attach a voltmeter to the
harness connector. Wait 4 minutes. Push and release the Harvest button. There should be full voltage at
the connector. If there is and the solenoid does not open, replace the solenoid coil. If full voltage is not
present, check voltage at the controller. If there is no voltage, check voltage from the controller to
ground. The hot gas pin is 5.
2. Test with an ohmmeter. Disconnect electrical power. Unplug high voltage harness from hot gas or
vapor valve. Measure resistance of hot gas or vapor valve coil. If open, replace the coil.
This light will be ON during harvest. Both
the Hot Gas Valve coil and the Harvest
assist solenoid coil will have power when
this light is ON.
November 2010
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