Centralair conditionersrely on fans to pull air through the condenser coils to dissipate heat.
These fans are subject to outdoor conditions and plenty of dirt and grime.
This is also a good time to inspect the fan blades and motor for signs of wear.
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Before You Begin
Air conditioners are high-voltage appliances.
You should always turn off the power to the unit before doing anything inside the compressor/condenser cabinet.
Turn off the power here.
Alternatively,turn off the breakerto the A/C system in your home’s breaker box.
If your system has both a breaker and a disconnect, turn off both.
Use a high-quality oil designed for high-speed motor shafts and bearings.
Do not use oil containing a detergent, such as automotive motor oil.
Detergent is bad for the bearings of fan motors.
Open Up the Unit
Remove the top cover of the compressor/condenser unit (the outdoor cabinet).
The motor is mounted to the underside of the cover.
The cover is usually secured with 8 or 10 screws along its perimeter.
Remove these with anut driver or screwdriver.
These ports will be located on the top and/or bottom of the motor.
A little up and down movement is normal, but there should be no side-to-side movement.
Finally, check each blade for cracks or other damage.
If you see any problems, replace the blade assembly.
Open Up the Ports
Remove the plug covering each oil port.
It helps to have an oil container with a small hose or nozzle.
Wipe up any spilled oil with a rag.
Reinstall the Plugs
Reinstall the plugs into the ports.
Spin the fan blade slowly by hand to disperse the oil within the motor.
Reassemble the Unit
Reposition the unit cover or fan cage and secure it with its screws.
Restore power to the unit.
Measure Guideline: Air Conditioner Diagnostics, Maintenance, and Replacement.
United States Department of Energy.
