When your air conditioner turns on and off repeatedly in short bursts, it’s doing something called short-cycling—and it’s not just annoying. Short-cycling puts unnecessary strain on your HVAC system, drives up your energy bills, and often signals a deeper issue that needs professional attention. At Clifford’s HVAC, we’ve seen it all. If your system is short-cycling, here are the top five causes to consider:

1. A Dirty or Clogged Air Filter

This is one of the most common culprits—and fortunately, one of the easiest to fix. A dirty filter restricts airflow, which can cause your system to overheat and shut down prematurely. That cycle will continue over and over until the filter is replaced or cleaned. We recommend checking your filter at least once a month, especially during Alabama’s high pollen and humidity seasons.

2. An Oversized AC Unit

Bigger isn’t always better. If your AC unit is too large for your home, it will cool the space too quickly and shut off—only to restart shortly after when the temperature climbs again. This constant on-and-off puts stress on the system and reduces energy efficiency. If your home cools too fast and never seems to maintain a consistent temperature, your system might be oversized.

3. Low Refrigerant Levels

Refrigerant is what your AC uses to absorb heat from your home. If levels are low—often due to a leak—your system may struggle to complete a full cooling cycle and shut off early. Low refrigerant also reduces cooling capacity, increases wear and tear, and can lead to expensive compressor damage if ignored.

4. Malfunctioning Thermostat

A thermostat that’s in the wrong location (like near a sunny window or heat source) or one that’s simply misreading temperatures can cause short-cycling. The thermostat may think your home is reaching the desired temperature too quickly and tell your AC to shut off before it should.

5. Electrical or Control Board Issues

Problems with relays, capacitors, or the control board can cause your AC to cycle erratically. These issues usually require a trained technician to diagnose and repair. If your system starts and stops at random times—regardless of temperature—this could be the cause.

Stop the Cycle Before It Gets Worse

Short-cycling doesn’t just reduce comfort—it can cut your HVAC system’s lifespan significantly if left unchecked. If you’ve noticed your AC is turning on and off more frequently than it should, don’t wait.

Call Clifford’s HVAC today for expert diagnostics and affordable solutions. We proudly serve homeowners across North Alabama with fast, reliable service that gets the job done right the first time.