Circuit Breakers

Circuit breakers protect both your air conditioner and the electrical system in your home. In many houses, the powerful compressor in the central AC is the biggest single consumer of electricity during summer season. Circuit breakers guard against excess current draw causing an overload, as well as mishaps like a short circuit.

Tons and Amps

Central air conditioners typically supply between 1.5 and 5 tons of cooling capacity, depending on the square footage of the home. Average residential tonnage is about 2.5 tons, and a central AC of that size typically draws around 12 amps at 220 or 240 volts when the compressor is running.

One AC, Two Breakers

Most central air-conditioner systems incorporate two circuit breakers. One protects interior components such as the air handler/blower fan inside the house. Another circuit breaker protects the outdoor condenser unit, including the compressor. This breaker may be included in the indoor breaker panel or by itself in an outdoor box mounted on an exterior wall adjacent to the outdoor unit.

Tripping and Resetting

The main sign of a potential circuit breaker issue is that the central air conditioner mysteriously stops and won’t restart. Here’s what to do if you suspect a tripped circuit breaker.

  • Check the two circuit breakers that serve the AC. If a breaker is tripped, the switch that should be in the “On” position will instead appear to be somewhere halfway between on and off.
  • To reset a tripped breaker, first switch it into the off position. Make sure to turn off both of the two circuit breakers that control the central AC, including the one in the box on the exterior wall outside.
  • Leave both breakers off for 3 to 5 minutes, then switch both back on again. Because many central AC compressors incorporate a reset delay, you may have to wait up to 15 minutes to determine if the unit will successfully restart or not.
  • If the AC does not restart — or the circuit breaker quickly trips again — contact your HVAC contractor for professional service.

For more about AC circuit breaker issues, contact Mowery Heating, Cooling and Plumbing.