Known for being highly efficient and providing improved air quality, Mitsubishi ductless mini-split heating and cooling systems offer comfort year-round for you and your loved ones. However, in order for these systems to work properly long-term, cleaning them regularly is essential.
If you’ve never cleaned a mini-split system before, knowing exactly where and how to clean the unit can be a bit confusing. And, what parts of the cleaning to leave to the pros. To clear things up, we have compiled a helpful guide on everything you should know about mini-split cleaning. After reading this article, you’ll be a pro at cleaning your mini-split unit and keeping it in tip-top shape!
Why is it Important to Clean my Mini-Split?
Cleaning your mini-split on a regular basis is essential for keeping it in good condition so that it operates at optimal quality. When a mini-split system isn’t cleaned for a significant amount of time, the potential for premature wear of internal components, mold growth, and the emergence of strange odors greatly increases. Furthermore, the presence of excess dirt, dust, or mold in your mini-split system can decrease the air quality in your home by circulating such pollutants into your living space.

Regular cleaning also reduces mold and mildew. By cleaning your mini-split ductless system, you remove contaminants in and around the coils that could lead to mold buildup. Much like dirt and dust, mold can drastically affect ductless system performance, causing cool air to come through the splits when you’re supposed to be heating your home and vice versa.
The higher the moisture content on the coils, the more bacteria will grow on your unit. If you live in a hot and humid climate (ahem, Maryland Summers!), your need for a cleaning is even more vital as this climate encourages mold growth.
What are the Dangers of a Dirty Mini-Split?
A dirty mini-split ductless unit can be hazardous, causing:
- Mold buildup. If mold is growing in your ductless equipment, the spores are carried throughout your home every time you turn on your unit. Mold can cause irritated eyes, headaches, runny noses, sore throats, allergic reactions, and other respiratory issues.
- Health problems. Even if you don’t have mold in your unit, you may encounter health issues due to dust, dander, and bacteria hidden in the unit. Children, elderly individuals, and those with respiratory conditions are at a higher risk.
- Dust accumulation. Dust that blows out of a dirty ductless unit lands on the surfaces of your home, exacerbating allergies and adding to your list of chores.
- Poor indoor air quality. When your ductless unit is dirty, everything inside is being pumped out into the air that you breathe every day, reducing the overall quality of your indoor air.
- Reduced efficiency. A clogged ductless unit cannot operate as efficiently as a clean one, wasting energy and driving up your electricity bills.
- Debris from a clogged unit can migrate to the drain pan. When it overflows, this can cause water to build up in your unit and lead to costly leaks.
- Expensive repairs. Dirt and grime causes your unit to work harder, decreasing its lifespan and increasing the cost of ownership.
What CAN I Clean on my Mini-Split?
There are a few maintenance tasks that should be completed regularly to keep your mini-split in optimal condition. One of the most important things is cleaning the air filters.
Mini-split systems have filters that catch dirt, dust, and allergens in the air. The filter is crucial to a ductless system’s function. If it’s clogged with dirt or grime, the system will struggle to pull in air, and your room will feel hotter or colder than it should. Plus, you’ll likely start to experience higher energy bills each month. If you have pets, you should be checking your filters more often, considering the hair and dander that pets can carry and shed. Cleaning the filters each month will allow your unit to run smoothly, and you’ll get the maximum return on investment for your ductless system.
You should also ensure the outdoor part of your mini-split is clear of debris, vegetation and snow. This way, the system gets proper airflow and doesn’t have to work extra hard to regulate the temperature.
How to Clean a Mini-Split Air Filter
If you have a Mitsubishi mini split, cleaning the filters is easy. Thankfully, this is a simple chore that you can easily take care of yourself. Just follow these five steps to get the job done.
- Turn Off the Mini Split: Before you remove and clean the air filter, you’ll want to make sure the mini split is turned off. This is a precaution that will protect both you and your ductless system.
- Open the Wall-Mounted Unit: Once you’ve turned your mini split off, you can open it up. To do so, gently lift the front panel until you hear a soft click. The panel should open easily and without force. Once open, you’ll be able to see the air filters.
- Gently Remove the Filters: There should be two air filters inside of your mini split air conditioner. With the front panel open, gently slide the filters out, being careful not to shake dust from the filters while removing them.
- Vacuum and/or Wash the Filters: Using a low-powered vacuum cleaner with a brush attachment, gently vacuum the filters. If there is any dust or debris left after vacuuming the filters, or if you do not have a vacuum cleaner to use, the filters should be washed by hand using lukewarm water. A great way to clean your air filter is by using the spray attachment on your kitchen sink. Once clean, let the filters air dry. They should not be placed back inside the unit until they are completely dry.
- Replace the Filters: When your filters are completely dry, slip them gently back into their original positions inside the unit. Then, close the front panel. Once the filters are back in place and the front panel is closed, you can turn your ductless mini split back on.
How Often Should I Clean the Mini-Split Filters?
We recommended that you clean your ductless mini split’s air filters each month, or more frequently if you have pets. Cleaning your air filters regularly will help:
- Improve indoor air quality
- Prevent mold in mini split
- Improve mini split efficiency
- Keep your home and family healthy
Cleaning your filters is essential to safeguard your ductless equipment and your indoor air quality. However, this step is not enough on its own and a yearly deep clean is necessary.
What Should I Leave to the Professionals?
A mini-split is basically an entire HVAC unit packaged up into a smaller package. That means smaller parts, tighter spaces and more room for mistakes if you try to tackle a deep clean yourself. A yearly deep cleaning of your mini-split is best left to the professionals!
Deep cleaning your mini-split system is a layered process that requires specialized cleaning equipment and technical knowledge. Before deep cleaning your system, our technician turns on the unit to check the air velocity and to make sure it’s operating properly. Then, they attach a catchment bag to the unit to catch the water and debris that will be generated by the cleaning process.

Next, the technician removes the cover and louvre to access the inside of the unit. They spray non-toxic cleaners onto the unit and use a pressure washer wand to push water through the components of the system. Typically, they start by cleaning the fins and the back of the chassis, followed by the back of the unit, the top drain, and the coil. To ensure the entire barrel fan gets clean, they spin the fan while cleaning this part, and then, they complete the process by cleaning any other interior parts and flushing out the debris that fell from the coil into the main drain.
Finally, they clean the the covers and louvres that were removed at the beginning of the process, and they replace everything and check air velocity and operation again.
After repeating this process on all indoor units, our technician cleans the outside unit using a very similar set of steps. Ultimately, this deep clean returns your ductless system to the same level of cleanliness it had when you first purchased the equipment.
When Should I Schedule a Deep Cleaning?
It’s important to have your Mitsubishi mini-split professionally serviced, or deep cleaned, at least once a year. This will help ensure that it’s operating efficiently and can help prevent any potential issues. The ideal time to deep clean is in the Spring or Fall…before it gets too hot or too cold. Don’t wait until you hear strange noises or see any leaks, prevent any issues by taking care of your system regularly.
How Much Does a Mini-Split Cleaning Cost?
The compact, efficient size of these units requires additional time, tools and attention to clean properly; therefore we charge on an hourly basis. The average time required to clean each indoor unit is one hour, and time varies depending on the level of cleaning required. Our hourly rate is $125/hour for each indoor unit.
If you have multiple mini-split units in your home, give us a call to get an estimate.
Leave the Cleaning to Pro-Tech HVAC Home!
Pro-Tech HVAC Home wants to ensure all our customers get the most out of their ductless investment. We know how busy you are and want to help take this task off your list once the installation is complete. Be sure to schedule your mini-split preventative maintenance to ensure you get the most from your new ductless system!
Pro-Tech HVAC Home is Your Top Rated Local HVAC Company!
When it comes to HVAC services, you need to work with a company with a stellar reputation for providing service that is guaranteed to solve your problems once and for all. As Annapolis’ Top Rated Local HVAC contractor, that’s what you get with Pro-Tech HVAC Home. Our customers rely on us for fast, friendly service at a fair price. Our #1 priority is keeping our Annapolis neighbors comfortable all year long!

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Pro-Tech HVAC Home offers new installation, replacement, repairs and maintenance of heating and air conditioning systems in the Annapolis area. Our customers rely on us for honest and reliable service for air conditioners, heat pumps, gas furnaces, Mitsubishi systems, and more. We’re happy to answer questions, troubleshoot, and help you choose the best HVAC system for you and your family. We’re always happy to help answer your questions, so please give us a call or send us an email.