Why Air Conditioners Freeze Up

Why Air Conditioners Freeze Up. A family happily playing in their living room.

Did you accidentally stumble upon your air conditioning unit operating, but the refrigerant lines are iced up?  You’re probably experiencing a freeze-up.

If you’ve noticed a thin layer of ice on the outside of your AC unit’s refrigerant lines, a freeze-up has occurred. This is not normal and indicates something is wrong with your system. It could be due to a lack of maintenance or a mechanical issue.

Remember that prevention is the best cure! Routine maintenance visits allow one of our Wm Price Heating Co. specialists to check for issues that could lead to freeze-ups. They also help your equipment run more efficiently, saving you money on utilities.

Even basic maintenance tasks like replacing a clogged filter can slash up to 15 percent off your energy bill. We recommend scheduling maintenance once per season, but it does not have to be pre-season. Having the air conditioning run for a bit before the maintenance is performed is beneficial. You are welcome to pre-schedule with us at any time. 

Why Air Conditioners Freeze Up

Freeze-ups happen when moisture forms on the air conditioner’s evaporator coil.  If the refrigerant temperature is below 32 degrees, this moisture will turn to frost and, on a long enough run cycle, eventually will turn to ice and freeze up to the compressor in the outdoor unit.  Here are a few common reasons this can happen:

Refrigerant Leaks

The refrigerant that circulates through your air conditioner’s coils removes heat and humidity from the air in your home. The refrigerant is at critical pressure and temperature. If that refrigerant level drops due to a coil or joint leak, your air conditioner will not operate properly.

The humidity in the air will condense on the cool evaporator coil and start to turn to ice. You may also notice reduced or no airflow.  Sometimes, you will see ice around the refrigerant lines or water dripping around your furnace.

Call Wm Price Heating Co. to schedule one of our heating, ventilation, and air conditioning (HVAC) professionals if you suspect a refrigerant leak. Your technician can then identify where the leak or leaks are occurring, what will be required to fix it, and restore the unit’s refrigerant to the proper level.

Poor Airflow

If liquid levels are not low, check the airflow. Sometimes, your evaporator coil freezes because something is preventing proper air circulation. The most frequent culprit is a dirty air filter. That’s why replacing or cleaning your air filter once monthly is best.

Alternatively, it can happen when objects block your vents, such as furniture or rugs. There may also be an issue with the blower that circulates the air or a dirty or clogged evaporator coil.

Temperature Setting / Mild Outdoor Temperature

Sometimes, the temperature inside the home or even outside can affect the operation. Setting your thermostat to low can cause your air conditioner to freeze up. The same can happen if the outdoor temperature is too low. It will lower the pressure of the refrigerant and can make your unit freeze up. Remember to turn your air conditioner off if the outdoor temperature is going to be below 55 degrees.

What Should I Do If My AC Freezes?

  1. Switch your air conditioner off at the thermostat. Additionally, turn the fan setting from auto to on.  This will allow the ice to melt and help to keep water out of your blower.
  2. Check for obstructions.  Make sure that the vents are not blocked by furniture or rugs.
  3. Inspect your air filter. If it’s dirty, it’s a quick fix. Simply replace or clean it. If it is a washable filter, vacuum it out or rinse it with water, allow it to dry, and then try turning the AC back on once the ice has melted.
  4. Call your HVAC specialist if the problem persists. If the filter and vents are fine, there may be a slightly more sophisticated mechanical issue. Call Wm Price Heating Co. to schedule a service appointment. One of our certified HVAC technicians can diagnose and repair it.

Need prompt and professional AC repair?

Wm Price Heating Co. is ready to assist you with your Girard, OH, heating and cooling needs. Call our office at 330-545-3722 or request service online.

Need HVAC Service?

Contact the experts at Wm. Price Heating and Cooling.

Call us at 330.545.3722!

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