Tecumseh AEA4440YXA Service Data Book page 61

A LOOK AT SERVICE SAFETY
Step 1: Before Continuing with
Troubleshooting...
Step 2: Disconnect Fan Motor or Any
Other Devices
Step 3: Check External Thermal
Protector
Step 4: Check Wiring
Step 5: Check Potential Relay
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.
If there is a fan motor or any other auxiliary device, open the
circuit for the fan motor or any other device.
Check for continuity across the thermal protector. If there is no
continuity, then the thermal protector may be tripped. Wait at
least 5 minutes, then check continuity again. If there is still no
continuity, replace the thermal protector.
Confirm that there is continuity between:
a. The power input terminal on the thermal protector and
5 on relay.
b. The protector common lead wire and C.
Before checking the relay, be sure it is mounted at the proper
position. (See pages 28-32.) Check the potential relay by mea-
suring continuity between:
a. Relay terminals 5 and 2. If there is no continuity, replace
the relay.
b. Relay terminals 2 and 1. If there is no continuity, then
the contacts are open. Replace the relay.
Possible reasons that a relay is not working properly include:
• Use of incorrect relay. Replace with correct relay.
• Line voltage is too high or low (greater than 110% or
less than 90% of rated voltage).
• Excessive short cycling. Short cycling can be caused by
problems with the compressor's thermal protector or sys-
tem components such as the thermostat, control, contac-
tor, or high or low pressure cut-out. For more information
on troubleshooting the thermal protector, see Step 3. For
troubleshooting the system components, refer to the OEM
service information.
• Vibration due to loose relay mounting. Tighten relay
mounting.
• Use of incorrect run capacitor. Replace with proper run
capacitor.
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Servicing