An iced-over air conditioning unit on a hot summer day sounds ironic, but it is a situation that many homeowners face each year. When your A/C system becomes frozen, it will no longer be able to do its job and remove heat from the air. No one wants to be sweating in their own home, so it is important to understand how to spot a frozen air conditioner and what steps to take to get it back up and running.

How Do I Know if My Air Conditioner Is Frozen?

A frozen air conditioner is when hot air flow is prevented in some way from reaching your evaporator coil. This causes ice to form either between your exterior wall and unit or within your A/C system. There are many different ways you can check to see if it is frozen over, one of the simplest of which includes putting your hand in front of the vent to see if it is blowing cool air. If it is not, you should proceed with checking your outdoor air conditioner for ice between the exterior wall and unit. Another sign of a frozen unit is condensation on the surface of the indoor unit or on the exterior of the condensate drain.

Causes of a Frozen-Over A/C Unit

There are various issues that can cause your unit to freeze over and it is important to know each of them, so that you can understand how to prevent ice from forming.

Dirty Air Filters

One of the most common causes of frozen air conditioners is allowing your air filters to continue to build up dust and grime. This is a problem because it prevents a steady flow of air from entering the system, which is an important step in delivering warm air to the coil. You can prevent this issue by changing your filter about every 30-90 days.

Low Refrigerant

Refrigerant is a special chemical blend that plays an important role in keeping your home cool. Typically, it is in a constant cycle of turning from gas to liquid to gas again, yet it never dissipates. This means that low refrigerant levels are usually due to a leak, and without adamant refrigerant, your A/C unit will likely ice over.

Clogged Drain Pipe

As your evaporator coil removes heat from the air, it creates moisture. If your drain pipe is clogged due to a build up of mold, sludge, dirt or even bugs, this moisture builds up and eventually can freeze.

Slow or Broken Fan

In order to keep your air conditioning system functioning properly, you must always be able to keep a steady air flow. If your blower fan is damaged or too slow, it won’t be able to effectively push warm air to the evaporator coil, causing it to likely freeze up.

Dirty Coils

Over time, if maintenance is not performed, your evaporator coils can build up too much dirt and grime. When this happens, they will struggle to do their job and not absorb all of the heat from the air. This can then cause the moisture in your unit to freeze over.

Closed or Blocked Supply Registers

Many people choose to close supply registers in their home thinking it will save them an extra buck on energy, but what they don’t know is that this causes a restriction of airflow and can ultimately lead to your A/C unit icing up. It is recommended that you do not close more than ¼ of your registers, or you may face issues. It is also important to ensure that curtains, furniture or other items are not blocking your supply registers.

What To Do if You Suspect Your A/C Unit Has Ice

If your A/C unit is not working correctly and you have suspicion that it is likely iced over, the first step you should take is to unplug it or turn it off. There is no reason to waste energy on the system fighting to remove heat from the air if it is not functioning properly. Next, remove any obstructions to airflow, such as curtains or furniture blocking your supply registers. Other than this, you should contact a professional to make any necessary repairs.

Take Measures To Prevent Ice From Forming

Though there are some steps you can take yourself, the best way to prevent an issue like this from happening is to schedule regular annual maintenance with an HVAC professional. If you are suspicious that your AC is acting up, schedule an appointment with Wyckoff ASAP.