Electrical Or Electronic Problems That Trigger Short Cycling In ACs

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Improper sizing is a common cause of short cycling in air conditioners, but it is not the only cause of the problem. Your AC has electrical and electronic parts. The malfunction of these parts can cause the AC to short cycle. Below are some specific electrical and electronic issues that can trigger short cycling.

Compressor Motor Malfunction

The compressor receives cool refrigerant and squeezes it to increase the refrigerant's temperature and pressure. The pressurized refrigerant flows out of the compressor and loses its heat to the surrounding air, thereby facilitating heat exchange.

The compressor runs on an electric motor. Physical or electrical damage to the motor can cause it to overheat. The motor shuts itself off to prevent damage if it overheats. The constant shutdowns cause the AC to short cycle.

Condenser Motor Malfunction

The condenser motor runs a fan that blows air across the condenser coils to cool the refrigerant. The condenser motor can overheat and shut down if it has malfunctioned. If that happens, the AC will shut down before it has cooled the house. The premature shutdown means the AC will switch on right again after shutting down. This behavior is the classic definition of short cycling.

Thermostat Malfunction

The thermostat readings determine when the AC starts and stops cooling. The cooling cycle continues until the house temperature matches the thermostat temperature. Thus, erroneous thermostat readings can lead to imperfect start and stop points for the AC

Here are some of the thermostat issues that can trigger short cycling:

  • The thermostat wires are loose
  • The thermostat is not properly calibrated
  • The thermostat is near a heat source
  • The thermostat is clogged with debris

Anything that causes the thermostat to send the wrong signals to the mainboard can cause the AC to short cycle.

Control Board Malfunction

The main or control board controls all the functions of the AC. The mainboard receives signals from the thermostat and controls the cooling functions of the AC. The operations of the mainboard depend on electronic circuits and devices. A malfunction of the devices can cause the AC to switch off and on without regard to the prevailing temperatures. 

Power Supply Problems

Lastly, the AC can also short cycle if it is not getting adequate power. The AC requires power to run its motors, relays, mainboard, thermostat, and other electronic and electrical parts. Inadequate power supply from the utility company, a damaged power supply unit, or even a loose wire can interfere with the power supply to the AC, causing it to short cycle.

For more information, reach out to an AC repair professional.