One of the most common, and unfortunately one of the most damaging, problems an air conditioner can experience is a condition called short-cycling. Short-cycling is both the symptom of a problem and a problem in itself. In some cases, a few simple adjustments from your HVAC pro can fix this issue. But in many cases, the root cause is serious and requires a bit more than just that.
And unless the short-cycling is stopped, it will lead to the premature breakdown of your air conditioner, prompting you to have to replace it much sooner than you planned. Plus, until that point, your air conditioner will have wasted a whole lot of energy and money.
The phrase short-cycling is HVAC speak for when an air conditioner (or any forced-air HVAC system) rapidly turns on and off without ever completing a full cooling cycle. Under normal circumstances, an air conditioner powers up the compressor and runs until the thermostat registers it’s met the desired temperature.
The air conditioner then powers down the compressor—but in a short-cycling cooling system, the compressor is stopped prematurely, before the end of the cooling cycle, then starts back up almost immediately. Why does this matter? When the compressor turns on and off like this, multiple times an hour, the air conditioner is in fact short-cycling, and this indicates that your air conditioner has a problem. What is this problem, you ask? Well, there are a number of possibilities, including:
- A clogged air filter
- An incorrectly sized cooling system for your home
- Low refrigerant levels (charge) due to a leak
- Air escaping through breached ductwork
- Miscalibrated thermostats reading incorrect temperatures
That first one we mentioned, a clogged air filter, is easy to remedy. In fact, changing your air filter every 1-3 months depending on the type of filter you have is something that homeowners can and should be doing on their own. But if you’re certain the air filter isn’t the problem, then we have to look at the other possibilities.
An incorrectly sized cooling system, unfortunately, can’t be resolved by anything but replacing the unit altogether. The other above-mentioned problems can be remedied with professional repairs.
As we stated above, not only does a short-cycling air conditioner signal a problem that already exists within the system, but it can cause further problems. These potential problems include:
- Your air conditioner uses the most power when the compressor starts up. So if your system is constantly cycling on and off again, it means you’re using and paying for more energy than you should have to.
- Your AC compressor accumulates more wear and tear the longer short-cycling goes on, and this can lead your cooling system to overheat and burn out as a result.
- If the air conditioner stops the compressor before completing the full cooling cycle, it won’t have sufficient time to actually cool your entire home, leaving you and your household uncomfortable.