56
Chapter 4
Step 1: Before Continuing with
Troubleshooting...
WARNING!
All electric power should be disconnected and
you should have already made sure that the compressor does
not have a ground fault (see “Checking for a Ground Fault”
on pages
47-48
).
You should have also checked the windings
for continuity and proper resistance (see “Checking for Conti-
nuity and Proper Resistance” on pages 48-49), made sure the
system is getting proper voltage, and that the control, thermo-
stat, and contactor are working properly.
Step 2: Disconnect Fan Motor or Any
Other Devices
If there is a fan motor or any other auxiliary device, open the
circuit for the fan motor or any other device.
Step 3: Check External Thermal
Protector
Check the external thermal protector by measuring continuity
between C and L on the starting and protector package. If there
is no continuity, the thermal protector may be tripped. Wait at
least 5 minutes, then check continuity again. If there is still no
continuity:
a. GE modules: replace the entire starting and protector
package.
b. TI modules: replace the thermal protector.
Step 4: Check Module PTC Relay
Check the relay by measuring continuity between the starting
and protector package pin holes where the R and S pins on the
compressor are inserted. If there is no continuity, the relay may
be open. Wait 3 minutes, then check continuity again. If there is
still no continuity, replace the protector package.
Step 5: Continue Troubleshooting
If all above tests prove satisfactory and unit still fails to operate
properly, check for adequate compressor pumping as outlined in
the procedure on page 83.