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Ductless Mini-Split Cleaning Tips: Essential Dos & Don’ts

Ductless Mini-Split Cleaning Guide: Essential Dos & Don’ts

Ductless Mini-Split Cleaning Tips: Essential Dos & Don’ts

A ductless mini-split system is a highly efficient heating and cooling system specifically designed to regulate the air temperature in a small area of a home. Due to the lack of ducting, these appliances utilize space very well and can be installed quickly and easily by a professional. 

Mini-split systems are available in single or multi-zone options. A single-zone mini-split system has a single outdoor condenser unit and a single indoor unit mounted on a wall or ceiling. A multi-zone system combines one outdoor unit with up to eight indoor units. Each indoor handler can control the temperature and air circulation of a specific zone or room in your home. 

Due to the customized control capabilities, these systems allow you to set specific temperatures for individual areas of your home. Not only does this make for a more comfortable environment, but it allows your home to be much more efficient in terms of heat distribution and energy use. A ductless mini-split system is an excellent addition to a new or existing residence.

Importance of Maintenance

Maintaining a household appliance or machine may seem a little daunting. Tinkering with the components, removing and replacing parts, and applying cleaning materials are tasks you might feel uncomfortable performing. However, proper maintenance of your system is crucial. 

A well-maintained and clean system ensures high air quality within each zone. A lack of cleaning allows bacteria and mold to develop. When the unit is in use, this bacteria can circulate the room, potentially harming the inhabitants of your home. 

A strict cleaning routine helps keep your unit running efficiently. One of the major benefits of mini-split systems is the SEER energy rating of the units. When dust and debris build, filters can become congested, making the system work harder to circulate air. The unit then consumes more energy, negating the SEER rating. Failing to keep your unit clean can result in costly repairs and replacements. By taking the time to maintain your system, you can avoid spending your hard-earned money fixing issues.

How Often Should You Clean Your Unit?

There is no specific amount of cleaning required for your mini-split system. It’s best to incorporate it as part of your regular home maintenance routine. Once per month is a good guide for an extensive clean. However, it may need maintenance a little more or less frequently, depending on how often you use the unit and the temperature outside. 

The most important factor is monitoring its condition, ensuring dust, dirt or grime isn’t building up. The following guide takes you through the dos and don’ts of cleaning your mini-split system to help you keep your device running smoothly.

remote control mini split

Dos of Maintaining a Mini-Split System

Position Your Unit Correctly

Although handy or knowledgeable people may be able to fit a mini-split system themselves, it’s highly recommended to hire a professional for installation. These systems require refrigerant lines, to connect the units, as well as electrical wires to power them. Refrigerant lines can be dangerous to tamper with. The lines must also be hooked up to a vacuum pump and be pressure tested by a professional before turning on.

It’s somewhat common for handy people to fit the units before hiring a professional to complete the refrigerant line installation. Professionals can also recommend the ideal position to install the unit, as the condenser and handler’s location can affect the system’s efficacy. 

Ensure that the outside unit is unobstructed and free of potential interference. For indoor units, try to leave at least 2.5’ of a distance between the appliance and any furniture. This minimizes the potential for clogging and reduces the amount of dust and debris buildup. It’s best to refer to each unit’s installation manual to ensure adequate spacing is provided.

Turn Off the Machine Before Cleaning

With an electrical appliance, safety is paramount. Before beginning the cleaning process, power off the unit, and switch the breaker off to ensure you’re not connected. Ensure you allow each unit time to cool before you begin cleaning. 

For the Leading Brands of Mini-Split Systems, Contact ComfortUp

Dust the Area Regularly

While you don’t have to clean your system each week, you should dust the room or area around the mini-split unit several times per week. Dust is a silent killer for air conditioning systems. If dust builds, it infiltrates your system, which can quickly damage filters and other internal components. This can lead to inefficiencies or the need for repairs and replacements. 

Monitor the dust levels in a room and wipe the unit’s exterior with a damp cloth to remove dust. Note where the vents are and ensure they don’t become clogged, by using a static dusting cloth to remove debris.

Clean the Condenser Coils

Clean coils are essential for the efficiency of a mini-split system. They are also prone to accumulating dirt, dust and mold, so you must keep them clean. The coils can be cleaned easily using a hose, cloth or both. Be careful that the fins don’t bend or warp. Remove any excess debris by hand using a cloth. You can also use a coil cleaner kit to tackle this task. After cleaning the coils, ensure that the unit is completely dried out before switching it back on. 

clean the filters

Clean the Filters

If the system filters are congested, it will struggle to run efficiently, ramping up your utility bills. Keeping the filters clear allows the unit to perform optimally, lowers operating costs and extends the appliance’s life. For the proper instructions on how to clean the filters, consult the product manual. 

To clean, carefully remove each filter, clear all the dirt from the unit and use a dry cloth to wipe away the dust build-up or a vacuum cleaner on its lowest setting with a brush attachment. Alternatively, you can clean the filters with clean water and soap. If the filters are damaged, or you’re struggling to remove the dirt, they might need to be replaced. 

Monitor the Drain Line

These plastic lines drain condensation from each indoor unit and should flow to a safe area outside. These drain lines do not connect to the outdoor unit.  If the drain lines develop clogs, then can potentially back up and the condensation water can leak from the indoor unit and make a mess inside. If these drain lines aren’t flowing normally, it’s best to call a professional.   

Clean the Exterior of the Units

Although your mini-split system’s interior contains the most critical parts for cleaning, maintaining a clean exterior gives the unit an extra layer of protection by reducing the amount of dust entering it. For the outside unit, get rid of any loose particles that have gathered around it. Remove leaves, sticks, mold, dirt or any other objects from around the appliance. Use a damp cloth to wash the cabinet and use some soapy water if dirt is hard to eliminate. Dry off the cabinet once you’ve finished cleaning. Be sure the system is powered OFF from the breaker before cleaning. 

Next, wash the fan cage. The cage can be cleaned using a cloth and brush. Again, clean them with a cloth and soapy water before drying them off afterward. For the interior air handler, simply wipe down the machine and keep it free of dirt and dust buildup. As for fan blades, only a professional should be handling and cleaning these as damage can easily happen and it can be dangerous. 

keep a cleaning checklist

Keep a Cleaning Checklist

There are several steps involved in cleaning your mini-split system. However, it is relatively straightforward and can be completed in a matter of minutes. To ensure that you don’t miss any of the steps, it’s good practice to keep a checklist. Remember to clean both the indoor and outdoor units.

Schedule Professional Inspection and Maintenance

Through regular maintenance, you can extend the life of your system and keep it in top condition. However, it is recommended that you hire a professional to inspect your appliance annually.  

You may detect that your system is malfunctioning through poor temperature regulation, strange noises or abnormally high utility bills. Unfortunately, some issues are more challenging to spot for most people. A professional technician can detect problems from subtle signs, saving you time, energy, and money in the future. 

For Affordable Heating and Cooling, Install a Mini-Split System from ComfortUp

Don’ts of Maintaining a Mini-Split System

Ignoring a Bad Smell Is a Bad Idea

If your system gives off an unpleasant smell, there is likely an internal problem. In most cases, this is because of a buildup of mold and mildew. The nature of a mini-split system means that it draws in moisture regularly. This can gather on the internal components, where the mold and mildew buildup. 

The coils are the most common areas for moisture to gather, so cleaning them should prevent this issue from occurring. You may not recognize a smell from your outdoor unit without intentionally checking on it. 

letting debris build up

Letting Debris Build Up Around the Outdoor Unit Can Cause Problems

Debris, vegetation, snow and other materials can quickly build up around your exterior unit. This often creates blockages, causing your unit to malfunction. If your system is having difficulty heating or cooling, it may be because of debris obstruction. A great way to combat this issue is to build a small cover to protect the unit. However, you must leave adequate space between the unit and the cover for ventilation. This is particularly effective in areas that experience annual snow.

Neglecting Using the Right Cleaning Equipment Is a Mistake

To give your mini-split system a proper cleaning, you need to use the right equipment. All the necessary items are common household products, so they are easy to find. Dry cloths, a bristle brush, dish soap, cleaning spray and water are the core products needed. 

Overusing Filters Is Counter-Productive

Filters are integral to keeping your mini-split system in good working order. Although regularly cleaning your filters is a good habit, you must pay attention to their condition. Filters will eventually break down and need replacing. Ensure you don’t overuse filters, by cleaning and replacing them when necessary.

Assuming the Interior Is Clean Because the Exterior Looks Fine Is Wrong-Headed

Regularly cleaning each unit’s exterior is a good habit, but it doesn’t prevent the interior from getting dirty. Your cleaning routine must be comprehensive. Make sure you regularly clean the inside and outside of each unit.

Neglecting Maintenance if the Unit Isn’t in Use Is Asking for Trouble

A lack of use doesn’t necessarily result in a lack of wear and tear to your system. Whether or not your unit is in use, you should carry out regular cleaning and maintenance. Mold, mildew and moisture can cause lasting damage. Pipes and components can become clogged, cracked, corroded or damaged from a lack of use and maintenance. Don’t wait until problems occur. Keep up your cleaning routine at all times, and ensure you don’t leave your mini-split system for more than a month without cleaning it. 

Forgetting to Hire a Professional to Inspect Your Unit Will Not Pay Off

Your annual inspection is vital for the condition of your system. Set reminders or mark your calendar to ensure you don’t forget to hire a professional to give your system a once-over. Some technicians can perform a deep clean in case you’ve struggled to get at the hard-to-reach spots. 

Forgetting to Hire a Professional

Extend the Lifetime of Your Ductless Mini-Split System

Most mini-split systems have a lifetime of between 12 and 15 years. Although purchasing and installing your system has an initial expense, the cost savings over time are significant. Through efficient heat management, you can enjoy the satisfaction of a reduced carbon footprint. 

Inadequate cleaning and maintenance can cause your system to run poorly or break down, decreasing efficiency and costing you money. Extend the lifetime of your mini-split system with a proper cleaning routine and reap the rewards through affordable utility bills and reduced waste.

For further information on mini-split systems, give ComfortUp a call today. Our expert team is on hand to assist you with all your HVAC needs, from deciding what system to purchase to care and maintenance advice. We provide affordable heating and cooling solutions through quality mini-split systems from leading brands, including Boreal, Mitsubishi and GREE.


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