How to Clean a Ductless Air Conditioner

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Updated February 12, 2023

Finding the best air conditioners means knowing what you need to create a comfortable living space. It also means knowing how to utilize the space you have. And in homes with ample wall space, that often means choosing from among the ductless systems. Also known as mini-split systems, like the Pioneer mini-split, they are great options. People with ductless systems must know how to clean a unit that has essential portions both inside and outside their home. That’s why these folks need to know how to install a ductless split air conditioner correctly. But to maintain their energy efficiency, you’ll want to follow these maintenance tips on how to clean a ductless air conditioner.


  • This type of indoor unit is intended to cool a small area.
  • Skipping routine maintenance can reduce the energy efficiency of mini-split systems
  • A well-maintained ductless air conditioner can also act as a heat pump through the heating season.

Ductless Mini-Split Air conditioner Cleaning

Ductless systems often have an indoor and outdoor unit portion. A good maintenance tip is to keep the outdoor unit portion clean of dust and debris. You can do this by regularly wiping it down with either a damp or dry cloth. While using a garden hose can help, do not soak the unit, as that much water can damage the unit when it is on.

Insider Tip

Keep the area around your exterior unit clear to avoid the amount of outdoor dirt that gets into the system.


A thorough cleaning process starts by turning off the system. This is important for your safety and the continued usability of the unit.


Make sure your unit is off before cleaning to avoid electric shock.


Besides regular dusting, service your ductless system’s outdoor unit during a deep clean as well. Focus on cleaning the air conditioning coil and the condenser unit. Luckily, you do not need a special cleaner spray for this task. A regular garden hose is ideal, and it is safe to use since the machine is off. Once you have washed off any debris, make sure the fins are still straight. If they have bent, realign them using a specialty comb. Make sure the unit is completely dry before you turn it back on.


Remove the air filters. Mini-split air handling systems often have more than one, so make sure you remember which filter goes into which position. To clean them, either rinse them with the hose attachment on a kitchen sink or use a brush nozzle attachment on a vacuum cleaner. Whichever option you choose, be sure you wear a mask, so you don’t breathe in particulates. Set the air filters aside to dry if wet.


Before returning your air conditioner filters to your unit, check the pipes that connect your system’s indoor and outdoor portions. These air handlers can become clogged with excess dirt, preventing your mini-split air conditioner from working. If they are dirty, wipe them down with a dry cloth or your vacuum’s brush attachment.


Ensure the unit is completely dry inside and out, especially around electrical connections. Return the filters to their places and unit casing to its original position, then enjoy your newly cleaned system.

STAT: It estimated a degradation rate of 2-3% per year without rigorous and regular maintenance. (source)

Every air conditioning system has a specific maintenance process. And it’s important to know how often to service your air conditioner. Centralized system owners must know how to check the Freon in a central air conditioner, for example. And knowing how to clean a window air conditioner is essential to saving money on expensive repairs.


Are ductless air conditioners noisy?

A ductless air conditioning unit is incredibly quiet. It produces only 25 decibels of sound, roughly equivalent to the wind blowing through leaves.

Do ductless air conditioners also heat?

A standard ductless system cannot produce heat. Mini-split heating and cooling systems, however, have a heat pump in addition to the evaporator coils that make cooling possible.

Are ductless AC units more efficient?

Newer units are of average efficiency, though they are often rated for a 400-450 square foot space at most.

What is a ductless mini-split?

It is an indoor temperature control system that cools indoor air in hot months and blows in hot air during colder weather.

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