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3-Zone Mini Split A/C Systems

3-Zone Mini Split A/C Systems

With its versatile approach in space cooling and heating, it is not surprising to see ductless mini split systems gaining wider acceptance across all segments of the HVAC consumers. In the residential sector, ductless system has presented new possibilities that essentially break the barriers in home cooling and heating that are previously deemed insurmountable, if not costly. Unviability of installation, impracticality of extending ductwork, and high-priced application are just a few that come to mind.

Already a great system for single-room cooling and heating, ductless mini split takes it a notch higher when it delivers innovative ways for whole-home climate control. To give you an idea how a ductless mini split system can effectively give you the freedom to have control over your temperature comfort at home, this article will be discussing how this innovative system excellently applies to a tri-zone configuration. If you have three rooms at home that need effective cooling or heating approach, read on to find out why going for a ductless mini split multi-zone system is your best option.

Understanding Ductless Mini Split

Despite being relatively new in the United States, ductless mini split system has created quite a large following and interest over the years, both in the HVAC professional segment and household consumer sector. While the other HVAC solutions like portable air conditioners, room air conditioners, heat pumps, central air conditioning systems, and other application-specific comfort solutions are great in their own right and definitely best in their own ways, nothing compares to the almost disruptive way that ductless systems have transformed home cooling and heating. Split-designed, ductless mini splits created the possibilities of having control over the temperature which you can hardly achieve using traditional systems.

Multi-zone Heating Using Ductless System

Ductless mini splits enable temperature zoning, which means you can divide the house in different segments or comfort areas. Unlike central air conditioner that make use of ductwork routed to each room and releases conditioner through air vents, a ductless system does not use ducts or dot the room with separated air vents. Instead, of ductwork, the areas targeted for cooling or heating will be installed with an individual air handler and one designated thermostat or remote controller. Connected to just one compressor or condenser unit that is installed outside the house, the air handlers can be controlled independently, allowing for regulated use of temperature according to personal preference or temperature demand. Typically, one condenser or outdoor unit can be linked with up to eight air handlers. This kind of flexibility allows for whole-home cooling and heating. Most importantly, this enables ductless mini split to present itself as the viable alternative to centralized climate control.

Zoned Comfort, Cooling or Heating a Three-room Environment

Let us say you live in a modest, one-storey home in which three main parts or rooms needed to be heated or cooled. If we will go by what most people used to do in these type of home—regardless of floor area or square footage of each zone—the most common cooling and heating system that will be used are any of the following sample configurations:
  • 1 through-the-wall air conditioner for the living room, 1 window air conditioner for a bedroom, and 1 portable air conditioner for the dining area.
  • 1 through-the-wall air conditioner for the family room and 1 window air conditioner each for the two bedrooms.
  • 1 portable air conditioner for the living room, one window air conditioner for the bedroom, and one through-the-wall air conditioner for the garage that you like to convert into a new, livable space.
  • 1 window air conditioner each for the three bedrooms (master bedroom and two bedrooms)
  • 1 centralized air conditioner for the whole home
In a tri-zone configuration using ductless mini split, you are basically installing three separate air handlers for three separate rooms. For easier explanation, let us again use the aforementioned sample temperature zoning setup; but this time, using ductless mini split. The following are examples of what you are supposed to accomplished using a mini split system:
  • 1 air handler each for the living room, bedroom, and a kitchen
  • 1 air handler for the family room and one for each of the two bedrooms
  • 1 air handler for the living room, one for one bedroom, and one for the converted garage
  • 1 air handler each for three bedrooms (master bedroom and two bedrooms)
  • 1 air handler each for the living room, one bedroom, and dining area
Through temperature zoning using ductless mini split, you will be able to control the temperature in each zone without affecting the rest. For example, if your living room is normally sun-drenched because you have large windows facing the direction of the sun every morning, you can choose to crank up the thermostat and set a higher cooling temperature in this specific room while maintaining the same level of temperature in the other two rooms. Or let us say that you normally do not use the other bedroom and just normally stay in the family room, and of course, master bedroom. In this case, you can set two different levels of temperature for the two rooms while the air handler in the other room is turned off.

Comfort Advantage with Tri-zone Cooling and Heating

Using temperature-zoning, you would be able to achieve the following benefits:
  • Personalized Comfort. You can set the temperature in each of the three rooms that you need to heat or cool based on your preferred degree of comfort.
  • Energy-savings. Being able to regulate the temperature enables you to cut your energy use and lower your power bills.
  • Greater Convenience. With the aid of designated thermostat and controllers, you can easily set the temperature in each room.
  • Versatile Application. If you decide to renovate your house, add a room, or convert an existing area into a functional space, you can simply add another indoor unit and connect it to the compressor.

How Much Should You Expect to Pay for a Tri-zone Ductless Mini Split Installation?

It is important to understand that ductless mini splits require higher upfront costs than traditional system. For a unit alone, you should have a budget in the range of $1,500 up to $5,000. Some really advanced ductless mini split models can cost you at least $15,000 or more depending on the size of the unit, the brand, the efficiencies, and other cost-influencing factors. When you add up installation costs, you can expect to pay at least $1,300 up to $3700 or more depending also in the complexity of installation. Additionally, some accessories may be needed, so you will again have an additional expense that amount to another thousand bucks, which is also dependent on the type of accessories. If you need to buy a new power outlet, for example, or an equipment stand for the outdoor unit, you will have to pay more. Additionally, the installation of additional accessories will also have an impact on the labor cost. For the electrical-related work, you might have to hire a licensed electrician. For a three-room ductless mini split installation, your expected expenses will be higher due to the following reasons:
  • The number of air handler to be used has direct impact on cost. The more air handler, the more expensive.
  • The installation will be a little bit more complex than just installing a 1:1 system or one outdoor unit for one indoor unit in a single room. With three rooms, you pay thrice the cost.
  • More zones mean more requirement or adjustment for accessories. For example, you will have to use longer line sets or electrical line.
Again, let use another example. Let us say, you will be using a Mitsubishi zoned comfort solution. Given the available offerings at ComfortUp, one system that you can choose is a Mitsubishi tri-zone floor-mount mini split air conditioner heat pump. This system has a capacity of 40,800 Btu and already includes one outdoor compressor unit, three air handlers, and three handheld IR remote controllers. For the whole equipment, it would cost you 17,135.96. This is real price and bigger than general estimate because it is one of the advanced systems with some really high efficiencies and cooling/heating capacities. It requires line sets which are not included in the package. As line sets vary in length, they vary in price as well. For this particular system, you will need at least two 1/4" X 3/8" line sets and 1 1/4" X 1/2" line set. With installation costs and expenses on other type of accessories and labor, you can expect to pay around $21,000 up to $25,000. If you will opt for the same brand but with lower price, the amount that can expect to pay for the equipment alone will be more than eight thousand bucks. A Mitsubishi tri-zone concealed duct mini split air conditioner and heat pump with a capacity of 27,400 Btu, for example, will cost you $7540.031. Including the average cost of installation, additional labor, and accessories, your total expenses would range from $11,000 up to 15,000.

Find Your Tri-zone Ductless Mini Split Solution at ComfortUp

For a great selection of ductless mini splits models with varying capacities for your tri-zone ductless mini split installation, you can visit



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