A Short-Cycling AC: What It Is, Why It Happens
In a recent post, we listed several of the signs your AC needs to have repairs from our professionals. One of those signs was when the air conditioner turns on and off too often, a phenomenon called short-cycling.
This is a common and major problem for air conditioning systems, so we want to take a close look at it here. Short-cycling can have multiple causes, any of which you’ll need to address before your AC suffers expensive, possibly permanent damage.
The Basics of Short-Cycling
An air conditioning system runs in cycles that begin when the thermostat sends a request for cooling. The AC sends electrical power to the compressor, which starts the circulation of refrigerant through the indoor and outdoor coils to move heat from inside the house and exhaust it outside. The fans also turn on to circulate indoor air and exhaust heat outdoors.
A standard cooling cycle will last for more than 15 minutes. This is how long it takes to change indoor temperatures. Most cycles will last for longer; it depends on how much heat the AC has to remove to reach the target temperature.
If an AC begins to run in cooling cycles that are 10 minutes or less, it’s not completing a full cycle. Something is causing it to shut down early. Because the AC won’t have enough time to make a major change in the indoor temperature, the thermostat will soon turn the AC back on, and repeat the cycle. This creates the rapid start-stop-start pattern of short-cycling.
We’ll get into some of the reasons short-cycling starts in the first place, but this phenomenon is harmful for the AC on its own. The continual strain on the compressor will wear it down and may lead to an early system failure. Because an air conditioner uses the most amount of electricity during start-up, short-cycling will cause it to drain large amounts of power and make the AC extra expensive to run.
The Causes of Short-Cycling
These are the most common reasons for an AC to short-cycle:
- A clogged air filter has been left in place. This is a simple one to fix: put in a new air filter. Remember to change the filter every one to three months to prevent this in the future.
- The air conditioner is leaking refrigerant. This places the entire system in jeopardy in the near future, as it will cause the compressor to overheat and burn out.
- The thermostat is malfunctioning, either sending incorrect signals to the air conditioner or misreading temperatures in the house as cooler than they really are.
- The air conditioner is extremely old (more than 15 years) and is approaching the end of its service life.
- The air conditioner was not properly installed and is too large for the space it’s meant to cool. It’s lowering the temperature so fast that it shuts down early.
In most cases, a short-cycling requires professional air conditioning repair in Dallas, TX. An air conditioner that’s too old or which was badly installed will need to be replaced. Our technicians will get to the root of the issue and resolve it for you.
Boone’s Heating & Air Conditioning, Inc. serves the North Dallas Metroplex. Call us for AC repair—we have emergency service available.