- Make sure your circuit breaker is turned on at least 24 hours before starting your A/C. Many units have crankcase heaters or utilize the windings in the compressor to maintain a minimum oil viscosity.
- Most residential air conditioners are not equipped to be ran at outdoor temperatures below 55 - 60 degrees. Besides potential damage to the compressor, system head pressure may be too low and cause problems such as ice to buildup on the indoor coil which in turn can cause damage to compressor valves and other components. Accessories can be installed to allow units to run safely down to well below freezing outdoor temps.
- Clear and debris from around the outdoor unit, especially coils and above the fan. Make sure there aren't any twigs, branches or other debris in the fan guard or fan blade. Carefully pull them out with the power off and look inside through the fan for accumulation of leaves or anything that will prevent proper drainage of rain.
- Of course always check your filter and replace or clean as necessary. Typically every 1-3 months for disposable 1" filters; 4-12 months for thicker 4"-6" media (air cleaner) filters, and 4-12 months for electronic air cleaners.