Common Reasons Why Your Air Conditioner Is Short Cycling

An air conditioner’s cooling cycle, very simply put, is the amount of time between the moment it gets turned on and when it finally reaches the temperature-programmed by the thermostat. Once the ideal temperature is achieved, the air conditioner shuts off, until it needs to turn on again for another cycle to maintain the temperature.

Sometimes, however, an air conditioner’s cooling cycle shuts down too quickly or operates in briefer cycles. This is known as “short cycling,” and there are several possibilities as to why it happens. Here are a few potential causes.

The air filter needs to be replaced

Over time, your air conditioning system’s air filters collect dirt and debris, keeping them out of the atmosphere of your home. When it gets too dirty or clogged, your air conditioner has to work harder to generate cooler air—which can make it overheat and put more stress on its working parts. That may result in its automatic shutdown.

Air filters should be entirely changed out no more than every 90 days—or even more frequently if you have pets or allergies. Replacing your air filter every month no matter what is always a good idea.

The evaporator coils are frozen or dirty

Evaporator coils are located beneath your AC unit’s air-blowing mechanism. Very simply put, they hold and convert the refrigerant that makes the AC unit run properly. If these coils get frozen (typically because the AC unit is running while it’s cold outside) or dirty, they can stop working and result in a short cycle. In that case, the coils need to be thawed or cleaned up.

Your AC unit is too big for your space

If your air conditioning system is too big or too powerful for the overall size of your home, it cools the air too quickly and shuts off sooner. While that may be great for the room your thermostat is in, it may keep rooms farther away from reaching their ideal temperature. Frequent shutdowns and startups can also put your AC unit through more wear and tear. Consider replacing a large AC system with a smaller, more consistent unit that uses less upfront power.

You have electrical or wiring problems

Faulty wiring, corroded connection points, or any number of electrical problems can prevent your AC unit from getting the power it needs to run effectively and smoothly. Especially if there are no other telltale signs of short cycling, you’ll need to contact your air conditioning service company to repair these wiring issues.

Your thermostat needs to be moved

The sensors your thermostat uses to detect room temperature can be influenced by more than just the internal conditions of the air. For example, if a wall thermostat is positioned so it gets hit by outside sunlight, it can shorten the length of your air conditioning cycle. Find an alternate location for your thermostat, one that’s clear of windows, kitchens, air vents, doors, or any other places that may experience rapid drops or rises in temperature.