What Causes My A/C Coils To Freeze

Reasons for AC Coil Freeze. This article outlines everything you need to know about frozen AC evaporator coils:

• • The major causes
  • The best way to fix them
  • The best ways to prevent freezing

East Valley residents know how important it is to have a functioning air conditioner, especially during the summer. That’s why you need to get help immediately if your AC evaporator coil freezes.

What is the evaporator coil? It’s responsible for cooling the air that’s circulated by your HVAC system. If the coil isn’t functioning properly, the refrigerant doesn’t cool and therefore can’t absorb heat. The result is a “running” AC unit that doesn’t affect your home’s temperature.

So, how can you tell if your AC coil is frozen, and what can you do about it? Here’s everything you need to know.

What Are the Signs of a Frozen AC Coil?

Since evaporator coils are inside the AC unit, you likely won’t know they’ve frozen right away. Instead, you’ll probably notice subtle signs, one of which is warm air coming from your vents. Of course, there are many reasons for failed cooling, so you should reach out to a professional for an inspection. You should also keep an eye out for the following signs, as they can help technicians pinpoint the issue.

Mysterious Puddles

If you start noticing random puddles in your home, you may assume you have a leaky pipe. However, unexpected water can also be the product of a frozen evaporator. This water will be near the drain line, which can get overwhelmed when there’s ice in the unit.

Higher Energy Bills

When your AC isn’t cooling, you can expect higher energy bills as your unit runs longer to achieve a lower temperature. If your utilities are much higher than usual, and you notice you’ve had to run the AC more frequently, it’s time to get an inspection.

What Are the Most Common Causes?

In most cases, air conditioning issues occur due to wear or dirt. This is true of frozen evaporator coils, which work in conjunction with several other moving parts. Since there are numerous possible causes, you should call a professional to take a look. Trained technicians know exactly what to look for and, in most cases, can solve the problem much more quickly than DIY attempts.

Refrigerant Leak

A leaking refrigerant line is a serious issue, as this component is rather complex. To cool air effectively, the refrigerant line needs to maintain a certain threshold of pressure. Otherwise, it allows the coil to get too cold, which causes ice to form.

Is it possible your refrigerant is just low? Due to the structure of the line, there’s no way for refrigerant to evaporate off. That means if the levels are low, there’s a leak. Fortunately, a professional can either pinpoint the leak and fix it or replace the line.

Malfunctioning Thermostat

Sometimes the issue isn’t the AC unit — it’s the thermostat. Faulty thermostats can cause a unit to run unnecessarily, and running too long can cause an evaporator coil to freeze.

Blocked Condensate Line

As the air cools, the moisture it contains begins to condensate. The condensate line drains this moisture away from the evaporator coil, usually into a drip pan. However, there’s nowhere for the moisture to go if there’s a block in the line. If this goes on long enough, it’ll start freezing around the evaporator coil.

Dirty Air Filter

Air circulation is critical to keeping the evaporator coil functioning as it should. As air moves across the coil, the refrigerant absorbs heat; if there’s no warm air to provide heat, the coil gets too cold.

What do air filters have to do with this? Air moves through the filters, which catch debris. If the filters are too full, they don’t allow optimal airflow.

How Can You Fix a Frozen AC Coil?

To ensure a quick and convenient repair, you should always contact an HVAC professional to fix this issue. However, there are a few things you can do in the meantime to minimize damage.

The first step is to stop running the air. A frozen coil puts stress on your AC’s compressor; continuing to run the AC can cause the compressor to fail. That means more expenses since you’ll then have to replace the compressor.

With the air conditioner off, the ice should naturally melt, especially if you’re dealing with the heat of an East Valley summer. If the ice isn’t melting, you can use a hairdryer to encourage it.

Of course, the melted ice can overwhelm the drain pan, so the last step is to clean up any overflow. You don’t want to leave water lying around, as it can cause significant damage to your home.

Replace the Filter

The air filter needs to be replaced regularly anyway, since it will naturally become clogged with dirt and allergens. If a dirty filter is the issue, you should see an immediate difference once a new one is installed. 

Clean Evaporator Coil

Sometimes all you need to remedy a frozen evaporator coil is to clean it. This process requires special training, so you should never attempt it yourself; instead, call a professional.

How Can You Prevent the AC Coil From Freezing?

An ounce of prevention is worth a pound of cure, especially when repairing your air conditioning. While some wear is inevitable when a machine has moving parts, there are ways to keep damage to a minimum and prolong the life of your AC. To prevent AC coil freezing, specifically, here are a few things you can do.

Get Regular Maintenance

HVAC maintenance has two parts: inspection and cleaning. Inspection allows technicians to spot parts that are getting worn or minor issues that can cause more significant problems later on. It can save you time and money since it enables you to prevent more expensive repairs.

Cleaning is equally important. As air conditioners pull air in, they’re also pulling in a variety of particles:

• • Dirt
  • Pollen
  • Mold
  • Mildew

These particles build up in the system, clogging components and reducing efficiency. When regularly cleaned, an HVAC system runs better and may even avoid significant issues such as a frozen AC coil.

Call a Professional If You Suspect a Problem

It’s easy to doubt yourself, especially when it comes to expensive issues. If you suspect your AC is acting up, you may be tempted to let it go, but that can lead to headaches and big bills later on. Instead, you should call a professional when you suspect a issue. Most HVAC companies offer free estimates, making it easy to determine if you have an issue.

Do you need HVAC repair? Then Superstition Cooling is the place to call. We’ve served the East Valley area for over a decade and are dedicated to offering the highest quality service to our customers. In addition to repair, we also provide installation and maintenance services for both air conditioning and furnaces. To learn more or to request an estimate, you can give us a call at 480-712-1597 or visit us online.

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