How to clean the indoor unit of your mini split AC

Noticing dust piling up on your mini split AC’s grilles? Maybe the air isn’t feeling as crisp as it used to. Sounds like it’s time to give that indoor unit a good cleaning. A little TLC will keep your AC running smoothly, improve the air you breathe, and make your home comfier. Let’s go through how you can safely clean the evaporator coil and filters yourself.

Just a heads up, the info here might not match your exact appliance model. We do our best to give helpful DIY repair tips, but different models can have different steps, error codes, parts, and so on. For spot-on guidance, it’s best to check your appliance’s manufacturer documentation or contact us if you’ve got any questions.

Why cleaning your mini split AC matters

Your mini split AC pulls in warm air, cools it down over cold evaporator coils, and blows the chilled air back into your room. But over time, dust, pet hair, and other bits and pieces can build up inside the unit, especially on the filters and coils. When too much gunk accumulates, airflow gets choked off, the system has to work harder to keep things cool, and the air quality can take a hit.

When the evaporator coil’s dirty, your unit has to work overtime, which hikes up your energy bills and wears out parts faster. And those clogged filters? They’re just blowing dust and allergens right back into your space. But if you learn how to give your mini split’s indoor unit a good cleaning, you can make it last longer, save on energy, and keep your home healthier. It’s pretty straightforward and doesn’t need any fancy tools or special skills, plus you’ll feel better knowing your AC’s in tip-top shape.

Before you get started, find out what model your AC is. Not sure where to look? Check out our how to find your appliance’s model number. Knowing your exact model helps you figure out any specific parts you might need and keeps things organized if you need replacements down the line.

Gather your materials  

Before diving in, make sure you’ve got all the tools you’ll need. Even though AC models can differ a bit, the essentials are pretty standard. Here’s what you’ll need:

• Soft cloths or microfiber towels
• Warm water mixed with mild detergent
• A vacuum cleaner with a brush attachment
• Fin comb or a soft-bristle brush for coil cleaning
• Protective gloves
• Compressed air canister (if you want to dust tight spots)
• Plastic tarp or towels to catch any drips

Prepare your mini split indoor unit

Before you start cleaning, clear out anything that’s in the way around the indoor unit so you’ve got space to work. It’s a good idea to put down a tarp or some old towels on the floor and over nearby furniture to catch any dust or drips. Look for the main panels or covers on the unit, they usually lift up from the bottom where there’s a little notch or handle. Once you pop off the front panel, you’ll usually see the air filters right there.

Grab a few small bowls or trays to keep any screws or fasteners you take out, you don’t want to lose those! It’s also smart to have a soft brush or microfiber cloth handy to gently dust off the edges of the cover before you completely remove it. That way, you won’t have dust flying all over your home.

If you come across any foam insulation or fragile plastic bits, be gentle so you don’t tear or break anything. Look out for any electronic parts like circuit boards near the panel; if you see them, be super careful not to get them wet. If your unit’s mounted high up, use a sturdy ladder or step stool to reach it comfortably. Just make sure it’s stable and that you’re not stretching too much to reach the unit.

Remove and clean the air filters

The air filters grab a ton of dust, and keeping them clean is one of the easiest and best things you can do for your indoor air quality. Usually, mini split filters are rectangular or square and sit right behind the front panel. Gently remove them by pulling outward or upward, depending on how your model is designed.

How to clean your filters:

1. Set the filters down on a clean, flat surface.
2. Use a vacuum with a brush attachment to suck up loose dust from both sides.
3. If they need more cleaning, gently wash them in warm, soapy water.
4. Shake off any extra water and let them dry completely before you put them back.
5. Look for any rips or tears. If you see any damage, you might want to replace the filter to keep things running efficiently.
6. Make sure the filters dry out completely before you pop them back in, that way you won’t get any mold or mildew. Putting a damp filter back can lead to bad smells and potential fungus issues. 
7. If your unit has more than one filter, just repeat the steps for each one. Clean filters help air flow better and can even cut down on energy use.

Clean the evaporator coil

Behind the filters is the evaporator coil, it looks like a bunch of thin metal fins. As air passes over these fins, it cools down and dehumidifies your room. Dust on the coil can block airflow and make your AC less efficient. Cleaning the coil takes a bit of care because the fins are pretty delicate and can bend easily, which can cause airflow issues. But don’t worry, a gentle touch does the trick.

How to clean the evaporator coil:

1. Check out the coil for any big debris or visible dust buildup.
2. Gently brush off dust from the fins using a soft brush or a vacuum with a brush attachment. Brush in the direction of the fins to avoid bending them.
3. If there’s still dust, you can use a can of compressed air to blow it away. Keep the nozzle a few inches back so you don’t damage the fins.
4. Lightly dampen a microfiber cloth with a mild cleaning solution and carefully wipe the fins, don’t soak them.
5. If you see any bent fins, use a fin comb to gently straighten them out.
6. If there’s stubborn grime that won’t budge, you might need a coil cleaner that’s safe for mini split units. Just be sure to follow the instructions on the cleaner. 
7. Avoid harsh chemicals, they can mess up the coil’s coating or damage plastic parts. 

Reassemble and perform final checks

Once everything’s clean and fully dry, you can start putting it all back together. Start with the evaporator coil area so you don’t get dust on your fresh filters. Carefully align each part in the reverse order that you took them off. Make sure the filters are sitting properly and don’t have any new tears.

How to put it all back together:

1. Give everything one last check for dust or moisture.
2. Put the clean filters back in their spots, making sure they’re facing the right way.
3. Close up the front panel or grille and secure it.
4. Screw in any fasteners you took out, snug but not too tight.
5. Take up the tarp or towels from the floor and around the area.
6. Turn the power back on at the breaker. 
7. Fire up the unit and listen for any weird noises. Make sure the airflow feels right and that it’s cooling properly. 
8. If you hear rattling or see error codes on the display, turn it off and double-check that everything’s put back together correctly. Often, if the filter or cover isn’t attached just right, it can cause vibrations or misalignment. A quick adjustment usually sorts it out.

Helpful resources

If you ever need replacement parts or more tips, swing by AppliancePartsPros.com, we’ve got a huge selection of genuine parts. We’re happy to answer your questions, and we’d love for you to follow us on social media for the latest appliance care and maintenance advice. You can find us on Facebook and Twitter. Feel free to reach out directly if you want personalized help with your mini split AC or any other home appliances. We’re always here to help keep things running smoothly.

If you come across more serious issues or need specific parts for your mini split, check out our repair help page or get in touch with us to make sure you’re getting the right part for your appliance.