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Top 5 Reasons Why AC Coils Freeze


Category: HVAC

Frozen AC coils, in contrast to other HVAC issues, can be brought on by almost any system flaw. It's certainly an issue if you notice frost or a film of ice on your indoor unit, but it's not always simple to figure out why.


We'll discuss the potential reasons of frozen air conditioner coils in this post, as well as what you should do if it has already happened to you.

Frozen AC Coils Indicators

If your indoor unit's coils are frozen, there will likely be ice or frost on them as well as maybe on the pipes. You might not be able to see that, though, as many interior units aren't accessible. What other signs of frozen air conditioner coils are there then?

  • Your first clue that there is a problem with your HVAC system is likely to be the heat. There are a few things you may check to learn more about the issue if your AC doesn't seem to be functioning as it should.

  • The airflow via the supply registers should be checked. Frozen coils may be the issue if the air is warm or completely stopped.

  • A buildup of moisture from frozen AC coils may result in condensation or water leaks in your building.

Continue reading to find out the top 5 problems that might lead to frozen AC coils.

1. Frozen AC coils may result from dirty air filters.

For your AC to work correctly, there must be a constant flow of pure air. Filters that are dirty might make it difficult for air to enter and exit.

The coils get too cold if air is not moving around them, which causes ice to build up.

2. Broken fans can obstruct airflow and lead to frozen coils.

It won't assist unless the fan is blowing air through the system, even if your filters are clean.

The lack of air flow caused by a malfunctioning fan motor or even merely filthy fan blades may result in frozen AC coils.

3. Blocked condensate pipes are the cause of frozen AC coils.

Your HVAC system's condensate lines are responsible for removing extra moisture caused by humidity. Through pipes, this moisture's water condensate makes its way to a floor drain.

A clogged pipe can cause water to become stationary and freeze. This is especially true if the obstruction is located close to the evaporator coil, which is the AC's coolest component. The water may freeze as a result of a clogged condensate line, which will then force the coils to thaw.

4. Frozen air conditioner coils result from malfunctioning thermostats.

Your thermostat and air conditioner work together to maintain a constant temperature in the building by monitoring the temperature frequently and adjusting how hard the air conditioner must work.

A malfunctioning thermostat could cause the air conditioner to run too long and wear out the system if it senses the temperature incorrectly or controls it inappropriately. If your building struggles to maintain a constant temperature or if it routinely runs too cold, you might be on to something.

Unchecked overuse of an air conditioner could result in frozen coils.

5. Coils that freeze frequently are caused by refrigerant leaks.

The substance called refrigerant flows through the AC coil of your air conditioner, changing pressure and temperature to absorb heat. If there is a leak, the reduced pressure will cause it to overheat. The coils then freeze over as a result, followed by the refrigerant lines.

In some countries, it is against the law to leave refrigerant lines leaking in addition to the fact that refrigerant leaks are terrible for the environment. Instead of just adding more refrigerant, a professional should rectify the leak or replace the coil.

What to do if your AC coils are frozen.

Okay, so you've established that the coil in your air conditioner is frozen. Even better, you might be able to identify which of the five factors contributed to your issue. How do you proceed from here?

The unit must first be turned off in order to prevent compressor failure.

Calling a specialist is in your best interest due to the potential for system harm. They'll be able to quickly identify the problem's root cause and restore your unit to operation.

While you wait for more assistance, you can take care of a few things on your own.

  • Find any water damage and clean it up. It's a good idea to clean up any water leaks from ice that your frozen AC coils may have generated in order to protect your building.

  • To melt the ice, try. You should switch off your computer and wait for the ice to thaw, or you can consider using a hair dryer. Never attempt to chip or chop the ice off as you run the risk of harming the coils.

How to prevent frozen AC coils with a preventative maintenance plan.

Do you think that worrying about all of this is unnecessary? Perhaps not, either. Obtaining a preventative maintenance plan is the simplest method to avoid AC issues.

An assessment and upkeep of your AC from an HVAC technician are included in preventative maintenance programs. When using your air conditioner for the first time in the summer or after turning it off for the season in the fall, these system checks are most helpful. Filter changes, coil cleanings, and leak checks are just a few of the maintenance duties that the specialist will handle.

In most cases, frozen AC coils are the result of a smaller issue that was neglected for an extended period of time. A preventative maintenance program would guarantee that you identify a problem as soon as it arises and have it fixed before it damages your air conditioner or leads to a more expensive issue.

It is more cost-effective to take care of your HVAC system over time with a preventative maintenance plan than to spend more money on major repairs. Additionally, it guarantees that no business is lost or work is interrupted by an AC failure. That means you can relax and get on to more important things.

Give Us a Call

Do you have a central air conditioning issue? Make a call right away! Our amiable team of professionals is here to provide you with quick, accurate diagnosis and repair.

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