What Causes an Air Conditioner To Freeze Up?

Published on: July 18, 2013

If your air conditioner freezes up, you may be at a loss to figure out what’s causing the problem. However, there are typically only three common causes. Read more about these three causes and how to solve the problem.

Three Common Causes for Frozen Air Conditioners

  • 1. Airflow Blockages – The most common reason for AC freeze-ups is a block to the movement of air. When anything restricts airflow inside your AC system, the cooling coil can’t release water as it normally would. When that happens, the water builds up on the coil much like condensation forms on the outside of a cold beverage. In turn, the coil then freezes the built-up water that should have drained away. First, check your air filter. If your air filter is extremely dirty, then air won’t be able to pass. If that’s the case, you’ll need to change your air filter more often. If it’s not the filter, then look for blockages inside your vents. Rodents, pests, debris and even toys have caused many AC freeze-ups. Simply remove any objects that may be blocking air movement. There may be considerable build up of dirt or grime inside the ductwork, so you should consider having your ducts professionally cleaned.
  • 2. Coolant Loss – Coolant exchanges temperature between the inside and outside components of an AC system. Also called refrigerant, Freon or Puron, your AC requires this chemical in a full amount to operate correctly. If coolant has leaked, the coil may freeze. While most coolant doesn’t have an odor, most manufacturers mix it with oil. Therefore, the smell of oil can indicate an obvious leak in your system. A professional HVAC technician can restore the coolant to the correct level.
  • 3. Cold Weather – You probably realize it’s not advisable to run your AC in cold weather. While most people don’t run it during winter, many overlook the effect of cool nights or other times when temperatures drop. If you sleep with the unit running overnight, then the outside temperature can freeze it. Likewise, an older malfunctioning thermostat can fail to detect the proper temperature at which to shut off the unit. In each instance, a modern programmable thermostat can solve the issue. The cost to install a new thermostat is much less than most emergency repairs. Plus, it will typically lower your electric bill by up to 10 percent.

Air Conditioning South East

Lower your electric bill by scheduling preventative maintenance on your air conditioner. A malfunctioning AC has to work harder and pull more energy to produce the same level of cool air. The professionals at Air Conditioning South East can put an end to your AC freeze-ups. We only work with companies who employ NATE certified technicians, the only professional certification recognized by the HVAC industry. You can have confidence that you’re receiving the best level of service available. Call us today.