The Importance of a Clean Evaporator Coil. Your Quick Cleaning Guide!

The Importance of a Clean Evaporator Coil For Your AC [2022] Phyxter Home Services

Like most people, you likely overlook components out of sight when performing annual maintenance service on your air conditioning system. One essential part often forgotten is the air conditioning unit’s evaporator coils. It might not be common knowledge, but when the air conditioner coils get very dirty, the system can become less efficient, resulting in eventual damage.

In similar cases, you’ll need the help of licensed heating professionals to guide you. According to, having a clean evaporator coil is integral to maintaining your HVAC system. Ideally, you have a basic idea of how your air conditioner works and the critical role evaporator coils play to appreciate the importance of cleaning them.

The Importance of Evaporator Coils

Phyxter HVAC tech installing a new evaporator coil in an indoor air handler
New Evaporator Coil Installation

The air conditioner’s evaporator coil’s primary function is to capture the heat from the air inside your home and transfer it outside via the condenser coil. Typically, central air conditioners consist of an evaporator coil located inside and a condenser coil located within the outdoor unit. Condenser coils (also known as fan coils) work by releasing the trapped heat into the air.

Heat Pump also works the same in summer. 

Typically, both the evaporator and condenser coils are made of copper. Several aluminum fins encase them to ensure heat transfer. Both coils can be found in different areas of the air conditioner system.

The importance of clean ac evaporator coils cannot be overstated, aside from providing the cooling needed to generate cold air. The evaporator coils also help in the HVAC system’s dehumidification process. As the coils become cooler, water condenses onto them and is removed from your home’s air. The water is collected in the drain pan while safely flowing away from the AC system through the unit’s drainage system.

Where is the Evaporator Coil Located?

The evaporator coil is situated inside the home, in the indoor air handler unit or air handler enclosure. The condenser coil is located in the system’s outdoor unit.

To get to it, you will have to remove the access panel.

The image below shows its location within the indoor air handling unit for most climate control setups in residential homes.

Central AC Evaporator Coil Location inside Air Handler

❄️ Performance and Effectiveness

Unfortunately, your air conditioner’s system performance and effectiveness dramatically reduce when you have dirty evaporator coils. Usually, the coils are damp from the dehumidification process, so pollen, dust, and other particles will stick to the coils.

However, if you have dirty air filters or there’s no air filter, the amount of contaminants that come in contact with the coil also increases significantly. With all the factors mentioned earlier coming into play, dust, and dirt can accumulate on the coils in just a short time. So, don’t forget to replace your filter regularly.

Other potential problems that can occur when the evaporator and condenser coils get dirty include:

  • Increased system wear (might lead to malfunctions and damage)
  • Possible ice buildup on the coil resulting in a frozen evaporator coil
  • Possible frozen refrigerant lines
  • Reduced cooling capacity
  • Lowered heat transfer
  • Higher operating pressure
  • Higher energy consumption
  • Higher temperature

When the coils are dirty, they can use up as much as 40% more energy than AC units with clean coils. Dirty coils can also reduce the AC unit’s cooling action by as much as 30%.

Left unattended, the AC unit will eventually become less efficient, and monthly utility bills will skyrocket. You must regularly check your evaporator coils and clean them as needed. At times, evaporator coils can collect debris and dirt quickly so that monthly cleaning may be needed. Typically, however, evaporator coils need to be cleaned every three months.

Without proper care and upkeep, you can spend money on air conditioner repair instead of maintenance.

Cleaning Your Air Conditioner Coil.

Top Tips on How to Clean Your Evaporator Coil

Use a Brush

brush cleaning evaporator coil

A brush can effectively remove light amounts of dirt from a dirty evaporator coil. Using a brush is also a great option since you are more in control of the pressure you will apply and the areas you are cleaning.

Using a brush also makes it very easy to sweep the dirt away. Brushing also allows you to scrub harder when needed. When using a brush to clean the evaporator coils, opt for a soft one so you won’t damage the fins.

Use Compressed Air

cleaning a ductless evaporator coil with compressed air

If the buildup of dirt on the evaporator coil is not too heavy, compressed air will often suffice. It is also recommended that the compressed air be directed opposite the normal airflow across the evaporator coil.

You must wear eye protection and use a shop vac when cleaning up the dirt and debris from an evaporator coil.

Use Commercial Cleaners

Cleaning ductless evap coil

When it comes to cleaners, you’d be delighted to know you have plenty of options available. Once you have chosen a brand, follow the manufacturer’s instructions.

Also, allow the cleaner to sit and foam until the debris and the foam is drained away. Reapply as needed or according to instructions or until the coils are clean.

Use Water and a Mild Detergent

cleaning ductless evaporator coil

If you don’t like using a commercial cleaner, you can try water and a mild detergent. Mix detergent with warm water and put the mixture in a garden sprayer or spray bottle.

Spray the solution onto the evaporator coils and let it soak for a few minutes to loosen debris and dirt. Use a soft cloth to wipe away any loosened debris. Reapply as many times as you deem fit.

Heavy Duty Cleaning

evaporator coil heavy duty cleaning

Heavy-duty cleaning chemicals might be your best option if your evaporator coils are so dirty.
You will also need a pressure washer or steam cleaner for heavy-duty cleaning.
Heavy-duty cleaning may also require more than a typical cleaning.

In other words, it can involve coil removal, cutting refrigerant lines, and reassembling everything afterward. So, heavy-duty cleaning is best left in the hands of a seasoned HVAC contractor.

✋ PRO TIP: Use low pressure if you must use a pressure washer.

Using a high-pressure washer makes it very easy to damage a condenser coil. The fins work as heat sinks during the heat transfer and are easily bendable. A licensed HVAC contractor will know how to clean it correctly without causing further damage. 

If you accidentally bend a few fins, you can use a fin comb to straighten them out. Do more damage, and you will need a replacement coil, which can be expensive!


  • The different supplies needed vary by the method used.


  • The tools required differ based on the technique used.

Dirty Evaporator Coil from customers indoor air handler
Don’t let this happen! Dirty Evaporator Coil from a customer’s indoor air handler

Final Thoughts on Maintaining Your Evaporator Coil

Phyxter Approved Logo on Service Truck

The importance of regularly cleaning your air conditioner’s or heat pump evaporator coils cannot be overemphasized. With routine upkeep and cleaning, you can keep your air conditioning systems functioning efficiently while keeping your utility bills low.

Now you know how to clean your evaporator coil to keep your AC running in tip-top shape, but if you still have AC problems, it’s time to call out the experts. Call the experts at Phyxter Home Services and learn how to keep your evaporator coils clean during the cooling season. Our air conditioning services are the best in the industry! Check us out and see if a Phyxter HVAC services technician is in your area.

Looking for a new replacement filter? Check out our next article and choose the right filter for your home: Air Filter Guide. MERV Filter Ratings and What They Mean For Homeowners.

Dealing with other common AC problems? Check out: Top 18 Common AC Problems and Solutions

Russell Jones

Russell, a native Australian and VP of Operations at Phyxter Home Services, is also part-owner of Vernon Air Conditioning, Plumbing, and Electrical Services. When he's not busy with work projects and renovations, Russell enjoys putting his vast knowledge of home improvement to good use by sharing his tips and tricks.

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Phyxter (pronounced Fix-ter) is a national home services brand specializing in Residential HVAC, Electrical and Plumbing solutions.

Phyxter is laser-focused on writing the best articles and guides to empower homeowners to get the best out of their homes.

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