You expect your air conditioner to do two simple things: turn on whenever the need for cool air arises and shut off once your home has cooled down enough. But what happens when your air conditioner turns on and it never stops running? Even on the hottest of days, your A/C system isn't designed to run continuously, so you definitely have a problem on your hands. Read on to learn what causes a runaway condition for your A/C unit and how you can stop it in its tracks.
What Causes A/C Units to Run Uninterrupted?
Air conditioners operate in cycles – they cycle on when the thermostat senses the need for air conditioning and cycle off once your home reaches a desired temperature. That's because the compressor is designed to operate at short to moderate bursts, and continuous operation could damage the compressor beyond repair.
Runaway A/C systems are quite rare, but are caused by a number of surprisingly common issues:
- Thermostat malfunction – A failing thermostat can send the wrong commands to the air conditioner, causing it to run endlessly.
- Airflow restrictions – A clogged air filter can stifle airflow, causing the A/C system to run for much longer than usual to compensate for the reduced airflow.
- Bad wiring – Damaged or poorly installed wiring can sever the link between the A/C unit and thermostat, preventing the unit from shutting down properly.
- Dirty coils – Heavy dirt and debris buildup on the condenser or evaporator coil can sometimes lead to a runaway A/C system.
- Deliberate misuse – Rigging up your A/C system to constantly blow cold air could prove bad for your unit's warranty.
- Improper size – If the A/C system is oversized for the application, it's possible for the unit to remain on for much longer than usual.
What Can You Do About It?
You can try correcting the issues mentioned previously with the help of your HVAC technician. In most case, repairing the aforementioned issues will restore your air conditioner to its normal operation. If your A/C system was recently installed, make sure the unit isn't oversized or suffering from defect.
If you have an older A/C unit, its current runaway condition may be a sign that it needs replacement rather than repair. Most A/C units offer a lifespan of 10 to 15 years before a replacement is recommended. If you've had your air conditioner in your home for 10 years or more, now is the time to consider contacting local air conditioning services and replacing it with a newer and more reliable unit.