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What Can Cause AC to Run Almost Nonstop

ac-grill

When the summer heat is intense (and this summer has certainly had those days!), you can expect your home’s air conditioning system to run steadily to keep your family cool. But no matter how hot it gets outside, no air conditioner should run continuously. ACs are designed to go through cooling cycles where they run until they’ve provided cooling to lower the house to the level set on the thermostat, then cycle down for a time and come back on. This helps to prevent the AC from overheating and stops the house from getting too cold.

But you may find yourself in a situation where your air conditioner is running all the time, much longer than the usual 15 to 20-minute cycles. This is a problem because it wastes energy and puts so much strain on the AC that it can easily overheat and break down. What can cause this, and what can you do about it?

An undersized air conditioner

First, is this a new central air conditioning system for the home? If so, then one possible cause is that whoever installed it (likely not a professional) failed to accurately size the unit to provide adequate cooling for the house. An undersized system won’t be able to cool the house enough and will continue to run as it tries to reach a temperature that’s impossible for it. The only “repair” for this is to have experts replace the unit with a correctly sized one.

Stuck relay 

The relay controls the flow of electricity to the air conditioner. When the relay is closed, it allows electricity to pass through, and when it’s open it stops it. If the relay becomes stuck in the closed position, the AC will not stop running as electricity will continue to flow to it. Technicians can clean the relay or replace it as necessary.

Malfunctioning thermostat

The air conditioning system might be fine, but the thermostat is sending incorrect instructions to it. One common cause of an AC that runs for too long is a miscalibrated thermostat that registers the home as hotter than it is. This will force the air conditioner to stay on for too long as it tries to make up the “phantom heat difference.” A thermostat can also lose the specific connection to the AC that it uses to signal the compressor to cycle down, leaving the compressor running nonstop. You’ll need technicians to repair or replace the faulty thermostat.

Low refrigerant charge

If an air conditioner loses refrigerant through leaks, the AC will start to lose its cooling capacity. As capacity drops, the AC must run for longer to provide cooling. Low refrigerant charge is a serious problem that not only threatens comfort, but it will also eventually cause the compressor to burn out and the AC to fail permanently. Technicians can seal the leaks and restore the proper charge.

There are several other causes that can create “nonstop AC,” such as dirty condenser coils and duct leaks. You can trust our technicians and their air conditioning service in Houston, TX to locate the exact problem and resolve it. 

Contact All Star A/C & Heating Services: Our integrity is our best, most used tool in our bag. 

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