How to Clean Air Conditioner Coils (12 Simple Steps)

To clean air conditioner coils, you have to take off the protective cover and reach in there to remove dirt and debris. When that is done, splash some water against the coils to loosen stuck-in dirt.

clean air conditioner coils

Keeping your AC coils clean is important as it lets the unit run optimally while using up less energy. In most cases, the ideal time to clean an air conditioner is in the spring. This gets it ready for some serious work in the summer.

To a lot of people, you’ll need air conditioner servicing to do this. What if we told you such an expense is not necessary? Well, that’s what we’re telling you.

Cleaning your AC coils is something you can do yourself! It won’t even take too much time an effort.

All you need to do is follow our step-by-step guide, from start to finish, and you’d end up with a clean dirty coil ready for work.

However, if you come across a fault while cleaning, then you’ll have to call air conditioner service for proper repairs. Unless you’re an expert, don’t attempt to repair an air conditioning unit yourself. With that cleared up, let’s get on with it, shall we?

Steps to Cleaning Air Conditioner Coils

Courtesy: DANDLINC

For the sake of clarity and organization, this process will be delivered in 2 sections: Accessing the condenser coils and Cleaning the coils.

Now let’s get started.

Accessing the condenser coils

1.    Turn off the power

This is the first thing you want to do. Never attempt to clean or maintain any electrical appliance without first cutting off the power. If you’re using an outdoor air conditioner, there should be a power box close by. Shut it off or remove the fuse. If it’s a window or some other indoor unit, you can just unplug it.

2.    Clean the area surrounding the outdoor unit. If there are plants growing nearby, it’s possible shrubs and sprouts grow and block the heating vent of your cooling unit. This will affect its effectiveness. Trim foliage to a distance of 2 feet from the unit to reduce the chances of anything growing into it.

3.    Remove the air conditioner access panel

This is where you begin to get hands-on. You will need a screwdriver or spanner to loosen the screws or bolts used to hold the cover in place. The right size will be indicated in the user manual, hopefully, you still have it.

Loosen them and pull off the access panel to expose the dirty coils of the air conditioner. Be sure to keep the screws somewhere safe.

Some air conditioning units have fans mounted on the grills. You have to remove that too. If it is fastened with screws, loosen than and keep in a safe place.

Now that you have access to the outdoor unit coils, it’s time to move to the next phase.

Cleaning the coils

1.    Clear out the drain passage

You must have noticed air conditioners output some water, right? There’s usually a drain pipe at the bottom of the unit or sometimes a pipe to through the water. That is what you’ll first clean. Make sure to check that it’s not blocked or it won’t drain the water you’ll clean the AC coils with. If it is clogged:

  • Pour half part water, half part bleach into the drain pan and give it time to clean through.
  • You can also get algae tablets for the drain. This will prevent algae from growing and clogging the pipe.

2.    Remove dirt and debris

If you peek into the unit, you’ll likely find dirt inside. Often times, leaves or bugs would have found their way in there. You want to clear those up first. You can use a vacuum cleaner for this if you want. Be careful with the fins on the coils. They bend easily and you need to keep them as intact as possible.

3.    Check for oil leakages

Most modern air conditioning units have designs that are maintenance-free. However, you still need to check underneath the compressor for oil leakages. If you notice any, you’ll have to contact an air conditioning service. Trying to tighten the motor or compressor will only worsen the situation.

4.    Spray the condenser coils with a water hose

Spray water on the coils to loosen stuck-in dirt. Don’t use a power washer or the force will be too much on the fins and will bend them; you don’t want that. Even with the garden hose, don’t spray the fins or the fan directly. As for the indoor air conditioning units, the next step shows you how to clean those.

5.    Use a foam cleaner on the condenser coils

Nu-Calgon 4171-75 Evap Foam No Rinse Evaporator Coil Cleaner, 18 oz.

To get yours, click here

You can use this one from Frost King. It works great for evaporator coils and reusable filters too. Use it directly on the coils and let it cover them up. If you’re cleaning the indoor side, you’ll use a no-rinse coil cleaner instead. This Sprayway is a great option, it even has a citrus smell.

6.    Allow some time

Once you spray on the coil cleaner, it will foam. let it covers the entire surface of the condenser or evaporator coils, leave it for 5 to 10 minutes. That is supposed to be enough time but it’s better to follow the instruction on the cleaner.

7.    Use a fin comb to clean the coils

3 Pack Fin Comb Air Conditioner Fin Cleaner, Air Conditioner Coil Cleaner Metal Fin Evaporator Radiator Repair Tool

To get yours, click here

A fin comb is a specialized comb used to straighten the fins of a condenser that are bent. With the foam still on, gently align the comb over the fins and run it down to put the individual fins back in place. This will also remove dirt and debris from the fins.

8.    Use a garden hose to rinse the cleaner off the coils

This step applies only to the cleaning done outside. Of course, you don’t want to be using a garden hose indoors. Once the waiting time has elapsed, run water over the coils to rinse off the cleaner along with dirt and grime.

If you used a no-rinse coil cleaner as we suggested, you won’t need to bother with the indoor side. Once you turn the AC unit back on, the cleaner will condensate off the coils.

9.    Reassemble the air conditioner

Now that you’re done with the cleaning it’s time to put things back in place and enjoy the cooling. If you took out the fan, put it back in. Ensure you fix the panel cover back properly before screwing it in. If everything goes as planned, the cooling unit will work better than it used to.

How to Clean Air Conditioner Evaporator Coils

TRUE 925139 Evaporator Coil Assembly

To get yours, click here

The evaporator coil is not so easily accessible like the condenser coil. However, you can still clean them. That’s where the advantage of the no-rinse coil cleaners come from.

All you need to do is spray it over the evaporator coil, give it time to do its thing, and then turn on the air handler.

While it’s working, the condensation on the evaporator coil will wash off the cleaner. This is the best type of cleaning you can do to the evaporator coils as you can’t get any closer.

You’ll need special tools to get the evaporator coil out as that is the only way you can thoroughly clean it. It’s not something you can do yourself, moreover, it’s illegal if you don’t have the proper license.

So, the method above is the best DIY cleaning you can do for your evaporator coils. Other than that, you have to call an air conditioner service company.

To avoid doing this often, ensure you use a good filter and keep your air ducts clean. This practice will keep your evaporator coils clean too. That way, you won’t be cleaning the coils as often.

Just so you know, these steps will help you clean the coils in a central air conditioning system too.


That’s it. All you need to know to clean coils in an AC unit. This is an important thing to do because it affects how well the air conditioner works. Our guide will help you clean both air conditioning coils. We also offered options to some of the tools you’ll need. So, you’re well covered. Even if this is your attempt, don’t worry. You got this!

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