SERVICING
S-7 CHECKING CONTACTOR AND/OR RELAYS
WARNING
HIGH VOLTAGE!
Disconnect ALL power before servicing or installing. Multiple power sources may be present. Failure to do so may cause property damage, personal injury
or death.
The compressor contactor and other relay holding coils are wired into the low or line voltage circuits. When the control circuit is energized, the coil pulls in the normally open contacts or opens the normally closed contacts. When the coil is
NOTE: Most single phase contactors break only one side of the line (L1), leaving 115 volts to ground present at most internal components.
1.Remove the leads from the holding coil.
2.Using an ohmmeter, test across the coil terminals.
If the coil does not test continuous, replace the relay or contactor.
S-8 CHECKING CONTACTOR CONTACTS
WARNING
DISCONNECT ELECTRICAL POWER SUPPLY.
Disconnect Electrical Power Supply:
1.Disconnect the wire leads from the terminal (T) side of the contactor.
2.With power ON, energize the contactor.
T2 T1
CC
VOLT/OHM
METER
L2 L1
Ohmmeter for testing holding coil
Voltmeter for testing contacts
TESTING COMPRESSOR CONTACTOR
S-9 CHECKING FAN RELAY CONTACTS
1.Disconnect wires leads from terminals 2 and 4 of Fan Relay Cooling and 2 and 4, 5 and 6 of Fan Relay Heating.
2.Using an ohmmeter, test between 2 and 4 - should read open. Test between 5 and 6 - should read continuous.
3.With power ON, energize the relays.
WARNING
Line Voltage now present.
WARNING
Line Voltage now present.
3.Using a voltmeter, test across terminals.
A. L2 - T1 - No voltage indicates CC1 contacts open. If a no voltage reading is obtained - replace the contactor.
4
3
OHMMETER | 5 | 1 |
2 |
TESTING FAN RELAY
4.Using an ohmmeter, test between 2 and 4 - should read continuous . Test between 5 and 6 - should read open.
5.If not as above, replace the relay.
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