Compressor contactor
1. Test using the controller’s indicator lights. When the unit is in ice making mode the
compressor contactor will have power. Check the Compressor indicator light, when it is on the
compressor contactor will have pulled in. If it is not, do a voltage check. Place voltmeter leads
on the coil of the contactor. There should be full voltage . If there is full voltage present and the
contactor has not pulled in, replace the contactor. If there is no voltage check if the high
pressure cut out is open. If the high pressure cut out is closed, check for voltage from the
controller to ground. The contactor pin is 4. Check from 4 to ground when the compressor
indicator light is on. There should be voltage. If not, replace the controller. If there is voltage at
the controller but not at the contactor coil, the harness wires or connectors are damaged and
must be replaced.
2. Test using an ohmmeter. Test the coil of the contactor for continuity or shorts to ground.
Replace if open or shorted.
3. Check connections and contacts. Be sure connections are tight and that the contacts are not
burnt. Replace any contactor with burnt contacts.
September 2006 Page 66
Test Procedures - Loads
This light will be ON when
the compressor contactor is
powered.
