How To Keep Your Air Conditioner From Freezing Up

frozen air conditioning

Home AC Freezing Up?

Nothing compares to entering a nice cool house on a hot summer day. On the same note, few things feel worse than having to swelter in the summer heat as you wait for an HVAC technician to come to fix a broken AC unit, not to mention that it’s going to cost you a few hundred dollars in repairs.

In places such as those in Florida, which experience the hottest summers in the country, a frozen AC unit can be a huge inconvenience. It will make your home very uncomfortable for you and your loved ones, and ruin your day really fast. Fortunately, with just a little regular effort, you can prevent your unit from freezing up.

How to Prevent Your Air Conditioner From Freezing Up
Clean and Change the Filters Regularly

Your AC has a filter that allows it to keep the air clean while it blows over the coils. The filter is necessary for two reasons, it helps to keep the air on the inside clean by getting rid of things like dust and pollen and keeps your unit from freezing.

If the filter is too dirty, it won’t capture these particulates in the air. As such, dust and dirt will build upon the coils over time until they can’t perform as they should. This will drop the temperature of the unit too low and cause it to freeze.

To prevent this, you have to change your air filters regularly. Most units stipulate the recommended timeframe for replacing filters – stick to this schedule to prevent your home ac freezing up and other potential problems.

Inspect the Condensate Drain Regularly

The typical AC unit will produce water as it pulls some humidity out of the air when it passes over the condenser. Some of this water is collected in order to help cool the surrounding air, while the rest is meant to drain at the back of the unit. However, if the water is unable to drain, the excess water will be passed through the coils over and over again. Water touching the coils will end up freezing, and the unit will stop working.

If this happens, you should find out why your unit isn’t draining excess water away. Remove the cover and the filter and check inside. If you find a clog or accumulated debris and dust, clean it up and let the water flow freely. If the inside is clean, try slightly tipping the unit backward to help it drain the water better.

Have the Refrigerant Checked

Your AC unit might freeze up because it’s running low on refrigerator fluid, or the fluid is improperly charged. This could mean that there’s a leak somewhere in the system, either because some joints and fittings are a little loose or some parts are rubbing up against each other.

In such a case, your best bet is to call a qualified HVAC technician to assess and service the unit. They can essentially refill the fluid, fix up any broken or loose joints and fittings, and perform proper maintenance to prevent future leaking and freezing issues.

home ac freezing up

AC Units Are Designed to Work in Specific Temperature Ranges

In Florida, many homeowners are often tempted to run the AC to cool down the house for other reasons unrelated to the air outside. A broken air vent, hosting big parties with lots of guests, or even kids playing around with the thermostat can all raise the indoor temperatures when it’s not really hot outside.

When you try to turn on your AC unit when it’s less than 60 degrees outside, it can cause your unit to freeze up. AC’s aren’t meant to operate at temperatures below 60, and the cold air blowing over the condenser coils can result in the coils freezing.

To prevent this, find other ways to cool your home if the outdoor temperatures are low, such as opening the windows (during daytime) or turning on a fan.

What to Do When Your AC Freezes

Here’s what you can do immediately after your AC unit has frozen up:

  • Shut off the AC from the mains to avoid damaging the compressor and wasting electricity.
  • As you wait for the ice to melt, check the condensate drain and ensure that it isn’t blocked.
  • Consider opening the ductwork and use a wet-dry shop vacuum to suction out the water.
  • You can speed up the melting by using a blow drier on the evaporator coils. Alternatively, you can turn on the AC fan without running the compressor to help melt the ice faster.
  • For window AC units, ensure that the unit is slightly tilted backward such that the melting ice is draining outside. From the outside, clear the condensate drain hole of the unit so that water can filter out.
  • Once the ice has fully melted and the drain pan is unblocked and empty, you can now turn on the AC. It should immediately start to work and cool off your home.
How to Keep Your AC Unit Running Smoothly

Regular maintenance and cleaning will go a long way in preventing freezing problems in your unit. So, regularly clean out any debris that enters the unit, change the air filters on schedule, and ensure your unit is serviced regularly. This way, you won’t have to worry about the coils freezing when you need them most.

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