Short-cycling is when your air conditioner turns on and off way too often. Your central air should click on for a few minutes at a time, four or five times an hour. If it’s happening more of ten, or if it stays on for a minute or less, there’s a problem. 

In this article, we’ll explain the difference between short-cycling and normal operation. Then, we’ll go through the four most common reasons for your central air to short-cycle.

You can likely fix the first two yourself. But, the second two will require a professional. 

And, we should mention that the best way to avoid problems like these is to get your air conditioner ready for the summer with a tune-up. A certified HVAC tech will make sure your system is in great working condition, and they’ll also fix any small problems before they get worse during the warm weather.

Not only will you get better cooling and lower bills. You’ll also extend the life of your system. That’s even more money saved in the long run – you’ll go a few more years without having to pay the cost of buying a new air conditioning system.

Meanwhile, if you have any questions about the HVAC system in your Boise, Eagle, Kuna, or Meridian, ID home, call or email us at Snowflake Air.

Why Your Central Air Turns On and Off

Your central air should turn on and off a few times an hour because the thermostat clicks it on when the temperature rises a few degrees higher than your call setting. Then, it keeps the system working until it gets a few degrees cooler than that setting. Broken thermostat can cause an air conditioner to turn on and off too often

It overshoots so that it takes longer for your home to get too hot again. If everything works properly, your system should run for a few minutes at a time. And, you should notice it turning on every ten to fifteen minutes. 

The exception to this is if you have a variable-speed or inverter system. You see this technology in ductless mini splits, but some high-end conventional condensers offer it, too. 

These systems use a slower speed or low-power mode to maintain the temperature all the time instead of correct. As a result, they run almost constantly. But, they’re virtually silent and use less energy. 

Four Possible Reasons Your Air Conditioner Keeping Turning Off and On

If the central air conditioner in your Meridian, ID home keeps turning off an on way too often, the four most common causes are: 

  • Your Thermostat is Broken

  • Your Air Filter is Clogged

  • The Air Conditioner is Too Small

  • The Air Conditioner is Oversized

Let’s go through these common signs of a broken air conditioner (or one that just needs some minor adjustments) one at a time.

Your Thermostat is Broken

Since the thermostat regulates when the system turns on and off, a problem with that appliance can cause short-cycling. 

You could just have a broken thermostat: An electrical short, a problem with the wiring, or just an old, worn-out model. The other problem could be calibration: It’s not measuring the temperature correctly. 

Either way, you can test this using a thermometer. Hold it up to your thermostat, and if the temperature’s don’t match, you’ve found the problem. 

Next, turn the setting way up so the room should be too hot. Compare the temperature to your thermometer, and see if the system kicks on when it should. You can go the opposite way, also: Set it to be too cold. 

If it’s turning on and off at the wrong time, you’ve likely found the problem. If you have an older digital model, it’s probably cheapest to buy another one. Or, if you’ve recently invested in a more expensive smart device, consider calling for repairs. 

Your Air Filter is Clogged

Another common reason for a short-cycling AC is a clogged air filter. That’s the screen designed to block all sorts of contaminants, mainly dirt and dust, from passing through your HVAC system. 

This process prevents that stuff from gumming up your heater or AC or circulating through the house. But, if you don’t change it every month — or at least every twelve weeks — it gets clogged. 

dirty vs clean hvac air filter

When that happens, it prevents air from passing through. Sometimes, that results in your AC sending warm air through the vents.

But, more often, your system will recognize something’s wrong, and turn off the system right away at a fail-safe. But the thermostat turns it back on because it’s too hot in the house. Then the cycle repeats.

The Air Conditioner is Too Small

A central air conditioner condenser that’s too small, or too weak, for your house will never cool it properly. You’ll end up with the AC turning on and off way too often because it won’t do the job right. 

Even if it does get cool enough, it’s not strong enough to really maintain that temperature. So, while it likely won’t short cycle, you’ll hear it turn on again very soon after it turns off. 

There’s no fix for this. At best, you can set it lower than you’d prefer to prevent it from wearing out too quickly. Then use fans or other “natural” methods to pick up the slack. 

The Air Conditioner is Oversized

The opposite of an AC that’s too weak is one that’s too strong. Yes, an oversized air conditioner is also no good: Your home won’t get cool, and the system will short-cycle. 

In this case, you get too much cool air at once. The sudden blast drops the temperature, and the thermostat tells it to shut off. 

But, you need a slow-and-steady stream of cooling to permeate the whole room. That maintains the temperature better. And the longer your system runs, the more it dehumidifies

An oversized system won’t deliver on these. And, it will wear out years before it should from all the extra stops and starts. 

Air Conditioner Replacement and Installation in Boise, ID

Don’t ignore a short-cycling HVAC system! The longer you let it happen, the more expensive the repairs will be as the problem gets worse. Call or email use at Snowflake Air for all your Boise, ID air conditioner replacement or installation needs. We serve the metro area with an excellent reputation for doing the job right the first time.