How Long Does It Take To Unfreeze A Central AC Unit?

AC unit

Here we are in the heart of the air conditioning season, which means Armstrong Plumbing, Air & Electric is getting countless phone calls about frozen AC units. Sometimes it’s hard to make our customers understand we can’t help them immediately no matter how uncomfortably hot it is inside their Lubbock, TX home. No work can be done until the ice has melted. Depending on how severe the buildup is it can take as little as one hour or as long as 24 hours. In our experience the higher number is more realistic.

How it Happens

In simple terms, your central AC will freeze up because the refrigerant is too cold and is freezing the moisture in the air as it passes over the evaporator coil, which is also known as the A-coil. There are two main reasons this happens:

  • Poor air circulation—Fans circulate air from the home over the coil containing the refrigerant. This is what removes the heat from the air and keeps the refrigerant at the ideal temperature. When there isn’t enough air circulation, the refrigerant gets too cold.
  • Low refrigerant level—This is another common reason an AC unit will freeze up. The low level is almost always the result of a leak that requires professional attention.

What to Do When it Happens

If your central AC falls victim to an ice-up, here is a checklist to follow:

  • Immediately turn the thermostat switch to off. Allowing the system to run in the cool cycle when it’s frozen can result in severe and expensive damage to the system.
  • Next, inspect your filter because an extremely dirty or clogged filter is the leading cause for air circulation problems. It’s another reason why regular AC maintenance is so important. If the filter doesn’t appear to be clogged, then you will need to call in an HVAC technician to diagnose the problem.
  • At this point the goal is to melt the ice buildup as quickly as possible so the technician can work on the AC unit. Go to the thermostat and turn the fan switch on. This will blow warm air across the coil to help thaw it out. NOTE: Fan switch only. Do NOT turn the AC unit back on (cool cycle).

An Ounce of Prevention

The best way to avoid a frozen central air conditioner, and many other problems, is with regular AC maintenance from Armstrong Plumbing, Air & Electric. Call now to schedule your appointment because living in Lubbock, TX means we have many more months of hot weather still to come. Be sure to like and follow us on Facebook and Twitter for more great information like this.