AC System Constantly Running

AC System Constantly Running

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We all know how bothersome and annoying it can be when our ACs constantly run, especially during the hot summer season. Because it is always hot here in Florida, understanding the common reasons why your AC runs constantly will be of great benefit to you and your electric bill. Your AC system may constantly run because of numerous reasons; however, these reasons may not be very serious. In this post, you’ll discover the common causes of AC constantly running and how you can prevent the problems.

Clogged or Restrictive Air Filters

One of the reasons why your AC could be running non-stop could be because the air filter is clogged. An AC system clogged with debris and dirt can restrict airflow into your home, which inhibits the overall performance of your AC system. When there’s insufficient flow of air over the coils, the system cannot cool the air or change the room temperature, so it keeps running constantly. Likewise, restrictive air filters; air filters that are too restrictive can reduce airflow, affecting your AC system’s functioning.

To get better airflow, invest in filters with lower MERV ratings. Filters should be checked at least once a month to know when it’s clogged with dirt. If your filter is dirty, your air conditioning repair expert can help clean or replace it.

Dirty or Frozen Evaporator Coil

Your evaporator coils are easily prone to dirt which can affect your AC system’s functioning by making it work harder to cool the air. Grimes easily buildup in evaporator coils and make it harder for the refrigerant to absorb heat from your home, even if you cleaned it a few months ago.

Also, your evaporator could be frozen if the unit is constantly running and supplying warm air alongside. If this happens, turn off the system and have a professional work on it. An evaporator coil is delicate so having an air conditioning service expert clean it with the right equipment is the best option. However, you can tell when it’s dirty by inspecting the outdoor unit to check for dust buildup and moldy odors.

Dirty or Blocked Condenser Coils

The condenser coils are located in the outdoor unit, making it even more prone to be clogged with debris, grime, and other dirt. When this happens, airflow becomes impeded, and the refrigerant cannot release air into the outdoor atmosphere. Like evaporator coils, condenser coils also need to be cleaned using a professional and the appropriate cleaning equipment.

Improper Unit Size

A properly sized unit would run efficiently and give you room the desired temperature. However, if your unit is not sized correctly for your space, it would not function well. Having an undersized AC unit means that your AC would keep running but still not deliver enough cool air. The AC works harder to cool your home, which can affect the life of your unit. You can tell when your AC unit is undersized when you keep acquiring high electricity bills, unequal circulation of temperature, and your room doesn’t feel cool enough. Note also that if your AC unit is too large, it will produce moist air. Even though it may run at a shorter duration, it would consume higher power which means higher power bills.

To get the correct unit size for your space, you’ll need an HVAC or air conditioning repair expert to perform a load calculation to determine the right unit size for your home.

Apart from the fact that Refrigerant leaks affect the efficiency of AC units, refrigerant can also be harmful to humans. It's also complex to repair; hence, you need an HVAC professional to find and fix the leak to enable it to function at its best.

Low Refrigerant Charge/Refrigerant Leak

Refrigerants are substances (gas/liquid) that transports air throughout your AC system. It absorbs hot air from your room and releases it into the outdoor atmosphere. Low refrigerant can occur when there’s a leak in the units, near the evaporator coils or the lines between the outdoor and indoor AC unit. When there’s a refrigerant leak in your AC system, the unit will run non-stop as it works harder to cool your home. You can tell when your unit has a refrigerant leak when you hear hissing sounds from the system, your room doesn’t feel so cool, there’s ice on the refrigerant line, and you pay high power bills.

Apart from the fact that Refrigerant leaks affect the efficiency of AC units, refrigerant can also be harmful to humans. It’s also complex to repair; hence, you need an HVAC professional to find and fix the leak to enable it to function at its best.

Your Thermostat Could be Faulty

Your system could just be running constantly because the thermostat is faulty. When your thermostat is faulty, the unit does not turn off when your room has reached the desired temperature; the thermostat cannot process the temperature of the room, so it keeps running. You can self-examine the thermostat by placing another thermostat close to the unit thermostat. Leave it for some time (say an hour) and check the reading. If it’s close to the correct room temperature, your thermostat could have a problem. You can troubleshoot by checking that your thermostat is correctly set to “cool,” or you could get an experienced air conditioning service expert to handle it for you.

leaky air duct with money coming out

Leaky Ducts and Other Air Leaks

Leaky ducts can make you lose cold air even before it gets to your space. Older ductwork especially may have poor insulation or loose joints, which can make cool air escape. When this happens, your room hardly gets the desired temperature, and the system keeps running to meet the desired temperature. Air Leaks through tiny openings in your home can make cool air escape, and you won’t get your desired temperature; hence the AC would have to run constantly to meet up with the correct temperature.

You can fix air leaks by ensuring that all tiny openings and crack walls are properly sealed; heck that the walls and roofs are properly insulated. If you think your ductwork might have leaks, you can get an experienced air conditioning repair expert to check it out.

Your AC System is Old and Need a Replacement

All HVAC systems have their life span. Although proper maintenance can help preserve their life span and make them more durable, they will still wear out eventually. When they become inefficient and wear out, you’ll need to replace them with an energy-efficient unit. Besides, new AC systems consume less power than older units; this will help you save more money. When considering getting a new AC system, check the SEER rating; energy-efficient systems have higher ratings.


Now you know the reasons why your AC is constantly running; the chances are that it could be any of the reasons above. Your AC running constantly means you’d be accumulating high power bills. It’s best to get a professional air conditioning repair or air conditioning service expert to fix the problem and save yourself from paying high power bills.

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Don’t Be Freezin’ This Season

AC units are designed to function in specific temperatures. Running your unit when the outside temperature is below 62° causes pressure inside of your system

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