On a hot summer day, a home’s central air conditioner is the largest electricity consumer, surpassing all other major appliances. Drawing about 3,500 watts per hour, a typical 2.5-ton central air conditioner imposes a heavy drain on the electrical system. If something goes awry, an A/C unit can visit a circuit breaker in the electrical panel, bringing relaxation in the house to an unexpected halt. Isolated causes like a short in wiring can kick off a circuit breaker, but recurrent overloads are probably the consequence of elements in the air conditioner malfunctioning and drawing too much electricity.
A three-ton residential central air conditioner circulates about 1,400 cubic feet of air per minute through the computer system. The workhorse that makes it happen is that the electric blower, found in the indoor air handler. Typically incorporating a quarter-horsepower motor that runs at about 1,000 rpm, the blower is a considerable electricity consumer. Worn or dry bearings in the engine can get the motor to bind, overheat and finally draw enough amps to visit a circuit breaker. Likewise a severely polluted system air filter can deprive the blower of atmosphere flow, also causing overheating and tripping a circuit breaker.
Evaporator Coil Icing
The evaporator coil that extracts heat energy in household air circulates vaporized refrigerant at a constant temperature of about 40 degrees. If excessive dirt and dust on the coil decrease the efficiency of heat exchange, the coil temperature might drop below freezing. This causes natural condensation that forms inside the coil to freeze. The Terrain coat of ice gradually strangles system airflow through narrow coil biting; ultimately, airflow is blocked. The complete reduction of airflow causes the body to run nonstop, never satisfying thermostat settings. In this situation, the overstressed blower motor — winding against the increased air pressure caused by the ice obstruction — overheats, causing a circuit breaker to trip.
Dirty Condenser Coil
Dirt and dust often settle on the condenser coil, found in the outdoor cabinet. Because the coil must be exposed to outdoor air, if it isn’t periodically cleaned, the dirt and dust buildup can become heavy enough to interfere with the proper release of heat energy in refrigerant circulating through the coil. If this heat cannot be efficiently distributed, the air conditioner runs for increasingly extended periods. This may eventually overstress the compressor engine or compressor, triggering the committed condenser circuit breaker.
Refrigerant transports extracted indoor heat outside to be spread by the condenser coil. The refrigerant contains the very important lubricant for the compressor, an electrically driven, 240-volt unit that is the largest consumer of amperage from the computer system. When refrigerant levels drop too low, insufficient lubricant reaches the compressor, resulting in severe overheating. The powerful electric motor in the compressor might bind, and the resultant extreme electrical draw causes a circuit breaker to trip. Since air conditioners don’t “use” refrigerant the same manner a high-mileage vehicle may have a gallon of oil, low refrigerant levels are almost always the result of escapes somewhere in the computer system.