2 Possible Reasons Why Your Home's Central A/C Unit Keeps Short-Cycling

Posted on: 20 October 2020


After noticing that your home is not as cool as you want it to be, you may have started paying attention to your central air conditioner. While observing it, you may have found that it is shutting off too quickly. Since the unit keeps short-cycling, the temperature in your home never reaches the one set on your thermostat. If this is the case, there are a couple of possible reasons why this short-cycling is happening as well as things you can try to remedy the issues.

1.  Unit's Air Filter Is Almost Completely Clogged Up 

One possible reason why your A/C unit keeps shutting off too quickly is that the air filter is almost completely clogged up with dirt, dust, and allergens. When the filter is clogged up, the air flowing through the unit becomes blocked.

When the airflow becomes blocked, the internal temperature of the unit starts to rise. As the temperature rises, the sensors read the overheating air and send a signal to switch off the unit before the excess heat damages the compressor or condenser.

Even if you do not see obvious signs of dirt and debris, try changing the air filter to see if this helps to improve the flow of air. Let the unit run for a few cycles to see if the short-cycling stops. If not, then another issue is causing the problem.

2.  Air Conditioner's Evaporator Coils Are Freezing Up

Another potential cause of the unit's short cycles is that the evaporator coils are freezing up. When the coils become covered in ice, the unit will shut down because the air inside of it is colder than either the environmental air surrounding it or your home's air.

One of the main reasons why coils freeze up is that you are setting the thermostat colder than the outside air and they are freezing overnight. After thawing out the unit, try setting the thermostat higher than the projected weather forecast's temperature to see if this corrects the problem.

If you have changed the air filter and the coils are not freezing up, there could be either an electrical problem or mechanical malfunction that is causing the issue. If you suspect that this is the case, you will need a professional to find and fix the problem. Contact an HVAC contractor near you who offers air conditioning repair services to schedule a time for them to come out to your home.