Welcome to Frequently Asked Questions page, here you can find commonly asked questions about what is ductless mini split system, where and how it can be installed, and how would a highly efficient ductless mini split system can reduce monthly energy use. Please browse listed topics, and remember to click “Back to top” to the top of this page:

Here you can find answers to most common questions:

What is a ductless mini split system?

A ductless mini split system is comprised of an indoor unit called the evaporator and an outdoor unit called the condensing unit.  The evaporator is connected to the condensing unit by copper tubing and electrical wiring which is passed through a 2 ½” – 3” hole.  Basically, it is a small central air unit with the flexibility of cooling or heating one room or more (zoning). See various ductless units configurations.

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How a ductless mini split system works?

Like conventional HVAC systems, the ductless mini split system locates the noisy compressor and condenser outside the house. But ductless mini split system eliminates the need for a basement- or attic-located evaporator unit and bulky ductwork by using thin copper tubing that pumps refrigerant directly to discreet wall mounted blowers inside. Even more remarkable, this same unit works in reverse in winter, absorbing heat from the outside air and moving it indoors to heat your home. The result – efficient cooling and heating for year-round, whole-house comfort in most climates.

Available in numerous mix-and-match capacities and configurations, there’s a mini split system for even the most difficult to heat and cool areas. See various ductless units configurations.

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What are the advantages of installing a ductless mini split over a central air system?

With Central Air you must cool an entire home when only one room may need cooling.  On the other hand, ductless mini splits cool only the areas you want and not the areas you don’t.

18,000 BTU is a typical minimum central air unit.  With inverter driven ductless mini splits, you can use as minimal as 3,000 BTUs.

Retrofitting homes requires cutting holes in walls, floors, ceilings or decreasing closet space with ducts.  Ductless mini splits require just a 3 or 4” diameter hole in the outside wall.  Means less mess and better home aesthetics.

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What is zone?

Typical homes are not zoned, or require complex zoning systems, which makes it very expensive for the homeowner.  With ductless mini splits, multiple evaporators make zoning as simple as setting a remote control.
Energy wasted in long lengths of uninhabited ductwork means higher energy bills.  Less than 5% cooling loss occurs in insulated refrigerant lines compared with up to 25% through ducts.

If two air handlers are connected to one outdoor unit the system is dual-zone, and triple zone means there are three air handlers connected to one outdoor unit. It is best to get an air handler for each room you are trying to cool but, if you are trying to cool open areas that consist of more than one room you may be able to use one air handler just make sure the BTUs are enough to cover the square foot area of all of the rooms.

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I want to cover-up the line sets running on the outside of my house, what can I do?

We carry a product called Decoline. It is a line set cover system, that comes standard in beige (ivory), white and brown colors. Many different fittings are available to create virtually any design. For more information, please visit www.ductlessdepot.net or call toll-free 800 590-1557.

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Can I paint the ductless mini split unit?

We do not recommend painting the evaporator.  If for any reason a problem occurs with the unit in the future, the manufacturer’ warranty will become null and void.

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Where can I purchase a ductless mini split system?

We can help you choose which system is right for you. Schedule a FREE In-Home Consultation with one of our Product Specialists or call 800 590-1557.

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What are the prices of your mini split systems and installation?

To find more about prices, schedule a FREE In-Home Consultation with one of our Product Specialists or call 800 590-1557.

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What is the warranty?

Mitsubishi product warranty as of April 1st, 2015 is 12 years (all parts and compressor), if installed by an authorized Diamond Contractor

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What if I need technical assistance?

We have assembled a team of the best technicians that are ready to assist you with any technical issue. Call us 800 590-1557 8:00 am – 5:00 pm EST Monday through Friday, and 8:00 am to 1:00 pm EST on Saturday (between May 1st and August 15th). Would you need an emergency help during off hours, call us 24 hours, or schedule your service call here

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Can I install a ductless mini split system myself?

Sure, you install. All ductless mini split systems come with installation manual.

Installation of a ductless mini split air conditioner is more complicated that a window unit but far less complicated than installing central air. You will need to run refrigerant lines for the coolant, wires electricity, and condensate line drainage. Please follow manufacturer instructions carefully. You will also need a properly trained and licensed person to charge it with the right amount of refrigerant. Call us for a Certified Start-Up by one of our manufacturer trained technicians – we will make sure that the installation was done correctly, evacuate and charge refrigerant as needed for your particular installation, check and start the system.

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How long does it take to install a ductless mini split system?

It all depends on the size on the system, complexity of your particular application and amount of ductless zones. Shortly – we have to look at your job. Schedule a FREE consultation in your home or office, our Comfort Consultants will help you create the most efficient design for your home.

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How often should I clean the filter?

The filter has a life span of 6 to 8 years and should be washed every 400 hours of use. The filter easily detaches to be washed with mild detergent.  Some models of indoor unit will notify you when it is time to clean the filter.  If the light is ignored, the unit will automatically shut down after 100 additional hours of use until the filter is washed.

We can help taking care of your new heating and cooling system. Enroll in our Service and Maintenance Program, and our Customer Care Specialists will send a technician to your home when it is time to clean filter. But wait, our technicians will also check the whole system per manufacturer’s guidelines to make sure it is safe to use and performs at peak efficiency.

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Do I need to clean the outdoor unit?

Let our technician check your system – schedule a Service Call. If cleaning is needed, the technician will show and explain to you in details. If our technician determines that cleaning is not needed – do not worry, and keep your money!

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What are EER and SEER Ratings?

The Energy Efficiently Rating (EER) is determined by The Air Conditioning and Refrigeration that equals the ration of cooling capacity in BTUs to the power input in watts. This rating determines the state of the air conditioner when it is up and running.

Seasonal Energy Efficiency Rating (SEER) is commonly used to measure central and ductless air conditioning. Higher energy efficiency equates to lower electrical bills.  All air conditioners must have a SEER rating of at least 13 to be sold in the United States.  Majority of systems we carry have much higher rating – up to 32 SEER. For more about SEER rating check AHRI Directory of Certified Product Performance

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What is a BTU?

BTU stands for British Thermal Unit, this unit of measure is used to measure cooling or heating capacity; 1 BTU is the amount of heat required to raise (or lower) the temperature of 1 pound of water 1 degree Fahrenheit.

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What is IAQ?

IAQ. stands for Indoor Air Quality.  Ductless mini split systems come equipped with various purification gadgets designed to remove airborne irritants, odors and allergens for a more comfortable indoor environment.

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How do I choose a mini split air conditioner?

Like choosing any air conditioner you need to know how many BTUs you need to cool the area you are trying to cool. You also need to consider the number of zones (air handles) you need – normally one air handler per room is what you would need but, if your home has open areas you may be able to cool multiple rooms with one indoor air handler.

There are many options and types of indoor units – some are mounted on the walls and some can be mounted in the ceiling. It is important that you talk to our Comfort Consultants about your options. They will help you decide which system would meet your needs.

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What are the pros and cons of a mini split air conditioner?

Mini split air conditioners is a cost effective choice to center air conditioning. They are typically more expensive than wall or window air conditioners and you need an HVAC professional to install the unit. Since the compressor sits outside they mini split air conditioners are very quiet and efficient.

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How big will the hole be in my wall?

This slightly varies depending on the unit you buy but, it is generally 2-1/2″ to 3″ in diameter.

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What is heat pump?

A heat pump function is similar to an air conditioner however instead of cooling the air like it would in the summer it heats the air and redistributes it into the room. It often will not work when it is colder than 0 degrees outside but, most ductless heat pump units heat at 100% capacity at 15 degrees. If heat is very important to you an electric wall-mount heater could be added to your room.

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What does Energy Star mean?

Energy star is a government backed program that backs products that are extraordinarily energy efficient. Products that meet strict energy efficient requirements determined by the EPA and the US Department of Energy that do not compromise the performance and features of a product receive the Energy Star logo. Fore more info visit www.energystar.gov.

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What is indoor unit noise level?

All air conditioners will make some sort of noise however the ductless air conditioners have been engineered to be quieter than other units. Mini split air conditioners are the most quiet since the compressor sits outside and indoor unit designed with a noise levels as low as 28 dB, which is compatible to a light breeze.

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What if my heating or cooling system is not working, is there anything I can do?

Yes, you can check simple things before making a service call:

    • Check disconnect switch. Make sure that circuit breakers are ON or that fuses have not blown.
    • Check for sufficient airflow. Make sure air filters are clean.
    • Check the settings on your thermostat (remote control). If you want cooling, make sure the temperature control selector is set below room temperature and the SYSTEM is on the COOL or AUTO mode. If you want heat, make sure the temperature control selector is set above room temperature and the SYSTEM is set to HEAT or AUTO.
  • Check if thermostat (remote control) batteries are in good condition. Otherwise replace with fresh batteries.

If these procedures do not work, contact us and our technician will be able to solve the problem!

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My ductless system is too old, the outdoor unit compressor is broken. Can I just replace an outdoor unit to save money?

No. If your system is old, chances are we will not be able to find a direct replacement. The new unit will not work with the rest of the system. Even if it could, would you like to sacrifice the efficiency of your system? You should seriously consider buying a complete new ductless system.

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What is the average life of a system?

Most systems have a lifetime of 10 to 15 years. As your equipment gets older, its efficiency can decrease dramatically. You may notice that it gets noisier and needs repairs more often. If your system is over 10 years old, you should have your ductless mini split system checked for maintenance or replacement.

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Should I repair or replace my system?

There are five main questions that need to be considered when deciding to either replace or repair your heating and cooling system:

    • How old is your system? If your system is more than ten years old, it may be wiser to invest in new, higher efficiency equipment, which could cut your energy costs by up to 40%.
    • What is the efficiency level of your current system? What was efficiency when the system was new? Unfortunately, replacing parts of your old system will not improve the efficiency. If the energy savings of using a higher efficiency system will cover all or part of the cost of investing in new equipment, you should seriously consider replacement of the old system.
    • What is the overall condition of your system? If your system is in solid condition, it could be wiser to simply repair it. But if your system breaks down often, you should consider replacing it.
  • How often is your system operating? If your system has been used extensively, it may be time to replace it.

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I am planning to move soon, can I take the system with me?

If you are moving in the next year or two and believe investing in a new indoor weather system will improve the value of your home, you should consider making the investment. If you plan to live in your current residence for many more years, it may also be wise to go ahead and invest in your future comfort.

For more information, please contact us, visit a showroom closest to you or fill out one of these request forms to schedule a Sales Call or Service Call.

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How can I lower my energy bills in the winter?

Here are a few simple tips for lowering your energy bills during the winter months:

    • Limit the loss of expensive heated air to the outside. Use kitchen, bath, and other ventilating fans sparingly.
    • Keep fireplace dampers tightly closed until you prepare to light a fire.
    • When using your fireplace, limit the amount of heated air drawn from the rest of the house. Open dampers in the bottom of the firebox if provided, or open the closest window about 1 inch and close any doors leading into the room.
    • Draft-proof windows, doors, and other air leaks. Caulking and weather stripping are reasonably easy, so you may be able to save money by doing the job yourself.
    • Lower your thermostat to about 65 degrees F during the day and 60 degrees F at night. For each degree you turn down your thermostat, you’ll save about 3 percent on your heating bills. Consider the comfort and convenience of an automatic clock thermostat to do this for you.
    • Keep your heating equipment operating efficiently. Clean the filter in your ductless heating system each month. Keep the heat pump system well tuned with periodic maintenance.
    • Insulate your attic floor or top floor ceiling to reduce winter heat loss.
    • Consider installing storm windows and doors.
  • If you have an attached garage, keep your garage door closed. This will prevent cold winds from infiltrating the connecting door and other areas between the house and garage.

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Why my air conditioning unit be blowing out warm air when my unit is set to cooling mode?

If the air coming out of the indoor unit is “room temperature” it could be something as simple as the outdoor unit is not running due to a tripped breaker, blown fuse or a simple electrical problem. If the air is actually warmer than the room temperature it is something more severe, the system should be shut down. In either case the system should be checked by a certified technician to find the cause of the symptoms.

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Can’t find what you are looking for?

Send your question. We will make sure an appropriate specialist follows up with you.

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