Your air conditioner should cycle on and off a couple of times per hour. If it's running non-stop or only switching off occasionally, this is a sign that something's not right. Here's a look at some of the more common problems that can cause an air conditioner to run constantly – and how you can address them.
The AC Unit May Be Too Small For Your Home
Is this the first summer you've used the AC unit? Or has it always run constantly through previous summers, too? If it just can't keep up with cooling off your home, this might be a sign that you have a unit that's too small for your home. Your HVAC technician may have made an error in selecting the properly sized unit for your home. Basic guidelines for AC size are as follows:
- 550 – 1,000 square feet: 14,000 to 18,000 BTU
- 1,000 – 1,200 square feet: 21,000 to 28,000 BTU
- 1,500 – 2,000 square feet: 30,000 BTU
- 2,000 – 2,500 square feet: 34,000 BTU
The number of BTUs your air conditioner delivers should be indicated on its label – or at least on your owner's manual. If the unit seems to be too small for your home, get in touch with the HVAC contractor who installed it. If they made an error in selecting the size for your home, they may compensate you for part of all of the cost of replacing the unit.
The Unit Might Be Dirty
If constant running is a new problem (your AC has run normally in the past), there's a good chance this is occurring because your air filter, condenser coils or both are too dirty. When the coils are dirty, your AC unit can't cool effectively, so it keeps pushing air into your home but never gets it cooled to the proper temperature. When the filter is dirty, airflow is restricted, which will cause the unit to run endlessly without lowering the temperature very much.
Cleaning your condenser coils is easy. Purchase a bottle of coil cleaner from a local hardware store. After turning off power to your unit, spray the coils down with the coil cleaner. Let it sit and loosen grime for an hour or two, and then rinse it away with the hose. Replace the AC filter with a new one, restore power to the unit, and see if the constant-running problem has been solved.
If your AC unit continues to run constantly even though it's the right size and you've cleaned it, contact an HVAC technician like Krewson-Sweeney Oil Inc. There may be an electrical communication issue between your thermostat and the AC unit, and this is an issue that will need to be professionally addressed.