Scotsman C2648 - Manual (Page 53)

C2648 Prodigy and Prodigy Plus Service Manual
January 2015
Page 53
Harvest Assist
Test using the controller’s indicator lights.
Harvest Assist Solenoid - No Longer Used on This Model
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.
Harvest Assist Motor
It operates much the same way as the solenoid only
using a small gear motor pushing a rod. You can test
the motor for resistance with an ohmmeter.
Hot Gas or Vapor Valve
Test using the controller’s indicator lights.
1. 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.
2. Shut the unit off by holding the Off button in for 3
seconds.
3. Unplug the high voltage harness from the hot gas
solenoid connected to the motor.
4. Attach a voltmeter to the harness connector. Wait 4 minutes.
5. 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.
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 when the Hot Gas Valve and
Harvest Assist have power.