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AC Running Nonstop? It Could Be One Or Both Of These Problems

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If your air conditioner runs nonstop, you might not know what to think about the situation. A number of things could be the culprits behind your cooling system's problem, including excessive indoor heat and a dirty evaporator coil. If your home builds up with too much heat, it can take a toll on your cooling system. A dirty evaporator coil can also be an issue if it stops removing warm air from the indoor environment. Here's what you can do.

Troubleshoot the Excessive Heat in the House

Sometimes cooling systems stay on longer than necessary when the outdoor weather is extremely hot and humid. Heat and humidity can build up inside the house and affect the performance of the indoor AC unit. The unit can't keep up with the cooling demands of your hot house, which causes it to work harder and stay on longer.

One of the things you can do is check your home's thermostat. Some homeowners place their thermostats on the lowest setting during the summer. If the thermostat is set too low, your cooling system may have a difficult time reaching that temperature. The system will run nonstop.

Try raising the thermostat by a few degrees. For instance, if the current temperature on the thermostat is 79 degrees, and you have it set at 74 degrees, raise the thermostat to 76 or 77 degrees to see if it makes a difference. Your cooling system might actually meet the new temperature setting. 

Also, go around your home and unblock your air registers and ducts. Sofas, tables, and even planters can prevent air from circulating through the home's air ducts. If you notice dust on the air registers' covers, remove it. 

If the cooling system doesn't lower to the new temperature setting or after you unblock your registers, you can try one more thing before you contact an HVAC contractor.

Clean the Evaporator Coil

The indoor unit's air handler uses an evaporator coil to draw warm air out of the house. If dirt, pet dander, and other household debris clog up the coil, air can't move through it properly. Some coils freeze up if they become blocked or dirty. You can check the evaporator coil to see if it requires a good cleaning. 

First, remove the air filter from the unit and examine it. If the filter is dirty, the coil might be as well. The air filter should keep contaminants off the coil, but the filter can fail to do so if you don't change it regularly or use the correct size. You can change out the air filter after you complete the steps below:

  1. Disconnect electrical power to your cooling system at the circuit breaker. 
  2. Place several large towels beneath the air handler to soak any water that leaks from the evaporator coil. 
  3. Pull out the drain pan, which sits just below the coil. If the pan is full, empty it into a bucket or toilet.
  4. Replace the drain pan, then uncover the evaporator coil. There should be a removable panel over the coil. Place both hands on the panel, then gently pull the panel until it comes loose from the air handler.
  5. Use a large spray bottle filled with about 4 cups of vinegar to clean off the coil. Saturate the coil thoroughly, then allow it to soak clean for 30 minutes.
  6. Place a fan in front of the coil to help it dry. 
  7. Cover the evaporator coil once it dries, then return power to the cooling system.

Wait for the cooling system to remove the heat from the home. If the temperature on your thermostat lowers, then you solved your problem. 

If the thermostat doesn't lower, and the AC continues to run nonstop, contact a heating and air conditioning contractor for assistance. You might have a problem with the outdoor unit as well. For more information, contact companies like Arnold Service Co.