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What Causes an Evaporator Coil to Freeze?

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If your air conditioning system doesn't meet your expectations, something may need to be fixed. A broken or malfunctioning air conditioner isn't good news when summer rolls around, especially if you live somewhere hot or humid.

Picture this: hot air outdoors, hot air indoors, and all-around humidity. 

If you live in Oregon, the days are long, but the summers are longer. Oregon isn't typically humid, but a faulty air conditioner can change that for you and your family at home.

A faulty air conditioner can cause various problems. For one thing, it can get intolerably uncomfortable basking in high levels of heat or humidity, and it could be all thanks to a frozen evaporator coil.

Here's how a frozen evaporator coil can impact the entire air conditioning system.

How Bad Can a Frozen Evaporator Coil Impact Our Home?

Most homeowners are surprised to learn their air conditioners suddenly stopped working due to frozen components. It is your air conditioner system's job to cool air, but it can stall or fail due to freezing.

Evaporator coils are some of the most critical yet overlooked components in any conditioner. A frozen evaporator coil can raise temperatures indoors higher than outdoors.

If it gets too hot inside, you can expect more than temperature and humidity levels to spike. A frozen evaporator coil can domino into various concerns, affecting the entire heat exchange process and causing costly AC problems. 

What is an Evaporator Coil?

It is an indoor coil that plays an integral role in the AC system. Most evaporator coils are made of copper. Copper is a great medium for retaining refrigerant and absorbing heat to transfer to a corresponding outdoor coil. The evaporator coil is inside the indoor unit, and the corresponding coil is found in the condenser (outdoor unit)

Evaporator coils work alongside condenser coils to manage heat energy appropriately. When an AC's evaporator coil gets dirty or stops working, it may stop absorbing heat, making it harder to cool your home's ambient air.

What does the Evaporator Coil do?

Have you ever heard someone yell, "close the door! You're letting the cool air out!" Keeping doors and windows open when the air conditioner is running makes your home harder to cool. However, that's not because of the cold air escaping.

Your home is taking longer to cool due to the heat penetrating your indoor environment. The more doors and windows open, the more outdoor temperatures impact those indoors. According to thermodynamics, the amount of heat particles is what determines temperatures. There are no "cold" particles, only a lack of heated ones, and that's how the evaporator coils help your HVAC system cool your home.

Evaporator coils absorb enough heat particles indoors to achieve your home's desired temperature indicated on a separate programmable thermostat. If you think about it, the familiar phase should be, "close the door! You're letting the warm air in!" 

However, there may be underlying issues if you don't have open ventilation systems or anything else, making things harder for the evaporator coil.

Common Signs of a Frozen Evaporator Coil

You may have a bad evaporator coil if your air conditioner system blows hot air or produces low system airflow. However, different AC problems may indicate frozen evaporator coils. Here are some of the most common signs your air conditioner system's evaporator coil isn't working properly:

  • Erratic energy costs
  • Excessive moisture from supply vents (creating condensation around the indoor air handler)
  • Air handler with low airflow
  • Air handlers or supply vents blow warm air
  • AC unit producing too much noise
  • The HVAC system is leaking from the inside
  • Air ducts are either frigid or hot to the touch

It is best to schedule a professional inspection if you notice any or all of these symptoms in your air conditioner. Typically, an evaporator coil cleaning can help eliminate these problems.

However, only some of your AC issues are due to dirty evaporator coils. Dealing with a frozen evaporator coil is more challenging than cleaning a dirty one. Still, there are ways to prevent them from bothering you. You can avoid frozen coil issues by routinely maintaining your air conditioning system.

Why Do Evaporator Coils Freeze?

Before looking around the AC for frozen coils, remember that a frozen air conditioner may stem from something as simple as a dirty air filter or faulty fan switch.

All appliances facilitating airflows, like a hand or hair dryer, have an internal blower fan. A malfunctioning blower fan is noisy, and you may be able to pick up on it quicker than other AC issues. If you hear banging or clanging echoing through air ducts and handlers, your AC's blower fan may be struggling. Dirty air filters aren't as easy to pinpoint and can snowball into worse problems, causing leaks and clogs.

Clogged air filters may even dislodge various components, which can be dangerous in a small closed system. Cleaning air filters regularly can prevent dirty coils and dislodged parts, protecting your air conditioning system from unforeseen breakdowns.

A clogged filter is only one of many things you should watch out for, and it may take too long to figure out more complex underlying issues. It would be best if you did not attempt to remedy most problems at home without the proper tools and techniques; it may be hazardous to your health. Professionals can help you detect minor concerns and effectively deal with more significant ones.

The Most Common Cause of Frozen Evaporator Coils

There may be one or a few reasons the evaporator coil freezes. Typically a leak, residual buildup, clogs, or faulty components is responsible for your frozen air conditioner. You may remedy some concerns at home, but different problems pose different risks. If you have to deal with the main reason (below) causing an evaporator coil to freeze, enlist the help of a professional.

Are You Dealing with a Refrigerant leak?

Refrigerant levels determine the overall functionality of your AC system. Your AC system can alleviate your home of scorching temperatures when the evaporator coil absorbs sufficient heat energy indoors. Low refrigerant may make it harder for the evaporator coil to perform. Running low on refrigerant is a typical wear and tear of all air conditioners.

While the AC system can still pull air, low refrigerant levels will not let the coil extract heat particles abundantly. However, you can correct that by replenishing the refrigerant supplyRefrigerant leaks are worse problems that deplete levels but cannot be fixed by replinishing.

What Should I Do About the leak?

Refrigerant leaks will freeze the evaporator coil, not only hindering its functions but completely preventing them. You may not notice refrigerant leaks quickly, but you should always remain vigilant for possible telltale signs.

If your air conditioner system on full blast still struggles to cool your home, it may indicate a frozen air conditioner coil. It is less likely to be the condenser coil, but it's best to have a professional make the determination.

Having an HVAC professional regularly inspect your AC unit can also prevent refrigerant leaks which may cause frozen evaporator coils, among other problems.

How to Avoid Frozen Evaporator Coils?

If you want to avoid your air handler giving you less during summer, ensure you practice proper HVAC etiquette: SCHEDULE PROFESSIONAL ROUTINE MAINTENANCE.

Proper Installation of Your Air Conditioner

Always turn to the pros when it comes to installing or maintaining AC units. Poorly installed air conditioning units may cause such problems down the line. Improperly placed components can cause dangerous hindrances. Blocked air ducts can hinder heating and cooling, causing you to spend more on constantly looking for internal issues.

Invest in the proper installation of your HVAC systems to lessen potential problems in the future.

Thorough Maintenance & Routine Tune-Ups

It's important to keep your air conditioning system in check all year. Ideally, you should run a maintenance check on your air conditioner before the first hot summer day hits. You might find something hindering your air conditioner from providing proper airflow.

A professional might uncover a dirty coil, overflowing condensate drain pan, fried circuit breaker, or damaged outdoor refrigerant line before it becomes worse.

Do You Need a Reliable HVAC Technician in Oregon?

You don't always have to call a pro to deal with a dirty air filter, but that does not mean you should do everything on your own. If you need help finding out what you might be dealing with and how to make them go away before this summer, trust Oregon's most reliable technicians!

Sunset Heating and Cooling | Electrical

Sunset Heating and Cooling have the tools, techniques, and drive to provide you with only effective yet efficient HVAC services. Don't hesitate to call in with all your concerns.

You don't have to risk a freezer burn in attempting to clean that leak. Leave your worries to us.

Whether you need ac replacement or ac refrigerant leak repair, we're there!

Call Us now at (503) 500-5866

What Our Clients Say

Sunset went out of their way to help with my project and David was amazing. Great job and look forward to future projects.

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Roman did an awesome job. I had the trifecta, new AC unit ,furnace and hot water heater. Courteous, and competent service. I highly recommend Sunset Heating & Cooling.

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Eduardo provided excellent service when he repaired our AC. I felt his effort was over and above expected. Polite and professional at all times. Good job!

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