As a homeowner with central air conditioning, it's important that you keep the system running efficiently and are attentive to any potential issues associated with its operation. One of the most common issues that may occur is an air conditioning system running persistently or not shutting down. Here are some of the reasons why this might be happening and what you need to know to address it.
Check The Fan
Sometimes, what seems like your air conditioning running nonstop is actually just the blower fan running, circulating air even when the air conditioner isn't engaged. The most common reason for this, aside from a mechanical malfunction, is the fan switch on your thermostat being left on.
Check the thermostat on the wall to see if the fan is set to "ON" or "AUTO." If it is set to "AUTO" already, and the air from the vents doesn't feel chilled like it should from the air conditioner, that could indicate a malfunction from the blower circuit. If the fan switch is set to "ON," that is why it is running. Switch it to "AUTO" so that it only runs when the air conditioner is running.
It is best to leave the blower fan on "AUTO" because it running full-time will lead to premature wear and tear on the system, potentially leading to an early failure.
Turn The Temperature Up
If it has been particularly hot outside, your air conditioner may be struggling to keep up and maintain the temperature that you've set on the thermostat. The same could be true if the unit is simply underpowered for the size of your home. Try adjusting the temperature on the thermostat by a few degrees. Even three to five degrees increase on your thermostat can make a big difference in the demand on your air conditioner.
If adjusting the temperature doesn't work, you may need to replace the thermostat. It may not be reading the temperature properly, causing the system to run constantly. However, the thermostat may not be the problem. If your air conditioner is too small for the size of your house, you may not be able to solve the problem without a central air conditioning replacement.
Inspect The Air Filter
The air filter on your air conditioning unit is supposed to remove particles and contaminants from the air as it passes into the system and over the condenser coils. That means the air filter gets dirty over time. As it gets dirty, it can hinder the air flow into the system. The reduced airflow makes it harder for the unit to function sufficiently, leading to prolonged operation. You should check and change the filters regularly.
If the filter has been neglected for too long, it can get heavily clogged and actually pull away from the sides of the air conditioning unit. When that happens, air blowing past the filter will reach the coils. The dirt and particles from the air will settle on the coils, causing them to freeze up and function inefficiently. If this has happened, you'll have to have the coils cleaned and replace the air filters to restore functionality.
Test The Refrigerant Pressure
Central air conditioning units rely on a specific level of refrigerant in the system to effectively cool the air. If a leak develops in the system, it can cause that refrigerant to escape, reducing the pressure and the system's ability to cool air. This can cause the air conditioner to run continuously in an effort to maintain temperature. You'll need to talk with an air conditioning contractor to find out if there is a refrigerant leak. The technician will test the pressure in the system, then find the hole in the system if there is one.
Speak to an air conditioning replacement technician to learn more.