22 Tips on how to clean your ac unit an easy to follow guide

April 24, 2023


22 Tips on how to clean your ac unit an easy to follow guide

Even if it’s still cool outside, it’s never too early to learn how to clean your AC unit. After all, you want your air conditioner to work well and run efficiently, especially during those hot summer months when you need it most.

What’s more, cleaning and maintaining your AC will ensure it lasts longer, but it can also save you money on your electric bills. According to Energy.gov, simply replacing a clogged filter can reduce your AC’s energy use by as much as 15%. 

Whether you have central air, a ductless minisplit, or a simple window unit, here is a straightforward guide to cleaning your indoor AC, outside unit, or window unit.

How to Clean Your Outdoor Unit (Condenser)

Step 1: Remove any debris from around your outside AC condenser. 

This includes anything that might clog up the system or get in the way when trying to fix it. Get rid of twigs, leaves, or overgrown grass. Your condenser should have 12 inches of clearance on all sides for the best efficiency.

Step 2: Thoroughly clean the fan blades. 

Cleaning air conditioner blower fans can be done with a vacuum or rag. 

Step 3: Check the mounting bolts. 

If any are loose, tighten them. Refer to the owner’s manual for specific instructions and tools necessary.

Step 4: Use oil or WD-40 on any fan motor oil ports.  

Wear a mask or do this in less windy conditions to avoid respiratory issues. Follow the manufacturer’s guidelines, so only the proper parts get lubricated.

Step 5: Soak up any water that’s inside or around the unit. 

A small puddle of water may accumulate under the condenser during hot weather when the system is working harder than normal. Clean up the water with a wet-vac or absorbent sponges, towels, or rags. If the condenser continues to leak, call Absolute Air to schedule a A/C maintenance.

Step 6: Inspect the refrigerant lines. 

These lines run from the evaporator coil on the air handler to the condenser. These are covered with foam insulation to help retain more energy. If you see that the insulation is damaged, replace it.

Can You Spray Down Your AC Unit? 

Yes, you can spray your AC unit, but be mindful not to get any of the chemicals on your unit’s electrical components. Some homeowners prefer to use a hose with a trigger-style nozzle to clean hard-to-reach spots. Be careful and avoid bending fins. You also don’t want to flood the unit and wet the fan or electrical components. Cover the electrical parts with a plastic bag. Use tie handles to secure the bags.

ac cleaner

How to Clean Your Indoor Air Conditioning Unit

Since not all air conditioning units are located outside, some knowledge is required to clean indoor units. Ductless Minisplits, unlike window units, are wall-mounted and placed in specific rooms that tend to get warmest on hot summer days. Here are some simple ways to keep them clean all year long.

Step 1: Shut off your electrical system. 

Turn off all power sources, so you don’t get harmed while cleaning. Find your AC’s service panel on the exterior condenser or compressor. This is a simple shut-off box near the unit. If you can’t find it, use your breaker box to deactivate the system.

Step 2: Replace or clean your air conditioning filters.

Every AC system has replaceable or reusable filters, which you’ll want to change or clean regularly. 

You can typically find the filter in the furnace or air-handler cabinets. Look inside or close to the back of the air-inlet side.

If you’re cleaning a reusable filter, wipe it down using a wet rag or towel. Make sure the cleaned filter is completely dry before inserting it back into the unit.

Step 3: Remove top and side panels. 

To clean your condenser coils, remove the side and top panels from the unit. These are also sometimes referred to as protective grilles. You may need a screwdriver or nut driver to do this. 

Be careful not to pull any of the wires connected to the internal fan. 

Step 4: Clean the air conditioning coils with a soft-bristle brush. 

Use a coil cleaning brush, refrigerator coil brush, or a soft-bristle paint brush, and start from the outside of the unit and gently clean the coils. When brushing, be careful not to bend or break any fins. If this happens, straighten them with a fin comb, which you can purchase at a hardware store. 

Step 5: Carefully vacuum the inside AC condenser coils. 

This can be done with a common household vacuum cleaner, so long as it has a tube that’s small enough to clean the delicate fins. 

Step 6: Use a coil cleaner to remove caked-on dirt and debris. 

Dirt that cannot be removed with a soft-bristle paint brush or rag and may require a little bit of coil cleaner, which you can purchase at an appliance parts store. Every coil cleaner is different, so be sure to follow the instructions on the bottle.

ac unit

How to Clean Your Window AC Unit

Step 1: Put on leather work gloves.

This will help you avoid getting sores or cuts when handling sharp equipment or irritants. 

Step 2: Unplug the unit.

If you are unable to unplug the unit, we recommend shutting off the power using a breaker to avoid electrical shock. 

Step 3: Remove the plastic filter holder or trim panel. 

It should easily snap off so you can remove the unit from your window or wall. 

Step 4: Remove the mounting frame and case. 

You can do this by loosening the case screws along the bottom of the unit. 

Step 5: Loosen and remove any debris.

Use a fin comb, soft-bristled brush, or vacuum to do this with caked-on dirt. 

Step 6: Gently fix any bent cooling fins.

Cooling fins can be difficult to replace, so take your time and be careful. A fin comb can help bend the fins back to their original position and can be found at a local hardware store.

Step 7: Spray foam coil cleaner over both coils.

If necessary, spray coil cleaner and brush toward the fins, so you don’t bend them.

Step 8: Clean the fan blades.

Use a towel and a household cleaner to wipe down the fan blades. 

Step 9: Oil any plastic or rubber-capped ports.

This will help keep them in good working order. 

Step 10: Wash or replace the air filter.

Washing or replacing the air filter will ensure your A/C unit is receiving enough air while it’s running. When you’re finished, put together any parts that were removed, and don’t forget to turn on the power! 

Next Steps

After cleaning the inside and outside AC units, turn the power back on. If you’ve cleaned a window unit, plug it back in. Now you are ready to enjoy a comfortable and cool space.

Cleaning your air conditioner should be a part of your regular appliance maintenance routine. This will help extend the lifespan of your unit and reduce your utility bill. 


If the cleaning process seems complicated or you are still unsure how to clean your AC unit, the HVAC experts at Yes! can help. Call today to learn more or to get a free second opinion.

Last Updated: March 28, 2024