How Many Mini Splits Do I Need?Mini splits can handle anything from hating and cooling a single room with a one-to-one setup, to treating an entire home with multiple units. So the question you might have is, “How many mini splits do I need?”

In most cases, technically you only need one mini split. The term refers to the heat pump outside and then all the air handlers inside that connect to it. 

Each mini split can have up to eight air handlers connected to a single heat pump. the capability of operating up to 8 zones, utilizing just one outdoor compressor.

If you want to heat or cool more than one room, you’ll need a multi-zone setup with more than one air handler. 

At that point, you may need two mini splits. That would be two heat pumps, each supporting different indoor units. Either way, you’ll need a professional to review the space and tell you how many indoor units are necessary. 

They’ll tell you what you need and also give you a good idea of what the system will look like when it’s installed in your home.

You’ll also want a professional HVAC contractor who’s certified to work on your mini split brand to handle the installation. While you can find the units online, they require a lot of HVAC and electrical know-how to be installed safely and properly. 

We can help you understand how they determine the number of air handlers you’ll need. Keep reading to understand more about how these systems work and how they’re configured.

And, if you live in Boise Metro or Valley County in Idaho, download our free product guide to learn more. Or, call or email us for a free consultation. 


How Many Air Handlers Do I Need for My Mini Split?

How Many Rooms Can A Mini Split Cool? (Ductless FAQ)

In order to provide the best information to give to your contractor, it is always a good idea to do your homework in advance to try to understand just what your requirements might be before your technician pays you a visit. 

The most asked questions concern two things – cost and how many do I need? Here are just a few of the frequently asked questions: 

  • “How many rooms can a mini split cool?”
  • “Do you need a mini split in every room?”
  • “How many square feet does a mini split cool?”
  • “How many BTU per square foot for a mini split?”

After all, a mini split system can last up to 20 years if you maintain in properly. So, you’ll want to ensure you invest in the right setup for your layout and for what you want. 

Read More: How Do Mini Splits Work?

    How Many Rooms Can a Single Mini Split Cool or Heat?

    A single mini split can heat or cool multiple rooms using multiple air handlers. connected to a heat pump. A single air handler can adequately a large, open-plan floor or a room with a high ceiling. But, the entire area must be considered an open space. That means no closed-off rooms or closed doors.

    In some cases, however, need a few smaller units for multiple points of airflow. Using larger air handlers – especially if the floor plan is not very open – might leave you with some hot pockets in rooms the farthest away from the air handler.

    With multiple units cooling your house, it’s easier to get a more consistent temperature throughout the house. 

    Do You Need A Mini Split In Every Room?

    You’ll need an air handler in each room you treat. Each of these units can cover a fairly large area. And, their built-in sensors and fans detect and treat hot or cold spots in the room. But, each one can only treat one enclosed space at a time.

    So, you can use a 1-1 setup (one air handler and one heat pump) for a single room. You’d need another air handler for every room or area of the house that’s seperated by a wall.

    Read More: How Much Does A Mini Split Cost for Homes in Boise, ID and Valley County?

    How Many Square Feet Does A Mini Split Cool?

    The most common air handler size is a 12,000 BTU unit. It can treat 450 to 550 square feet. On the lower end, a 9,000 BTU model handles 350 square feet. A 36,000-BTU air handler can treat up to 1,500 square feet.

     How Many BTUs Per Square Foot For a Mini Split?

    Mini Split Installations In Meridian, ID | Snowflake Air

    The number of BTUs that your system will consume is the determinant of how many mini splits you will need. It is that simple. But determining how many BTUs requires some simple math. Here is how it is calculated:

    1. Based on the size of your home, calculate the BTU requirements (primary factor). Usually, we use a 20 BTU per sq ft rule of thumb. Example: For a 1,500 sq ft home, you would need 1,500×20 = 30,000 BTU output. You can use one 30,000 BTU mini splits, two 15,000 BTU mini splits, or three 10,000 BTU mini splits.
    2. Be aware of the airflow and access to different rooms (secondary factor). Matching the cooling output (BTUs) is not enough. If you have a larger space, the airflow from a single 30,000 BTU mini split, for example, won’t be able to flow into all the rooms adequately. You will be left with hot pockets and uneven temperature dispersion. Having closed doors also prevents the cool air from coming into a closed room.

    Read Real Case Studies Of Mini Split Installations In Boise Metro and Valley County

    Based on these two factors, we can quite easily determine how many mini splits you need. We are going to show you how to calculate the BTUs, which mini split indoor handler sizes you can choose from, and how many mini splits you need for how many rooms.

    • 1 outdoor unit. This is where the compressor and all the power come from.
    • Several indoor units or air handlers. 1 outdoor unit can power 1, 2, 3, 4, 5, 6, 7, or even 8 indoor air handlers. We call this 1-zone, 2-zone, 3-zone, 4-zone, 5-zone, 6-zone, 7-zone, and 8-zone mini splits, respectively. Indoor air handlers can produce anywhere from 9,000 BTU to 3,6000 BTU (3-ton) cooling output.

    Keeping it simple, a rule of thumb is that you need 20 BTUs for every square foot of living space assuming an 8ft ceiling.

    This simply means that you need to multiply the square footage of the area of your home you want to cool by 20 BTU. It is important to note that to adequately cool or heat multiple rooms, doors need to be kept open to allow for the free movement of airflow.

    Example 1: How many BTU do you need for a 1,000 sq ft house? How many mini splits for a 1,000 sq ft house?

    BTU Requirement (1,000 Sq Ft) = 1,000 Sq Ft × 20 BTU = 20,000 BTU

    In this example you can get the coverage that you need with the following two schematics:

    • 1-zone mini split with 24,000 BTU air handler. This is a bit more than 20,000 BTU required but it’s better to have a bit more than a bit less.
    • 2-zone mini split with 9,000 BTU and 12,000 BTU air handlers. The combined cooling output is 21,000 BTU; very close to the 20,000 BTU required.

    Read More: Rebates and Financing Options For Treasure Valley Heat Pump and Mini Split Installations


    Heat Pump And Mini Split Installation In McCall, ID And Boise Metro

    If you are like me, I like to have my calculations double-checked by a reliable source who are experts in the business. But these few tips will give you some basic information to be able to ask questions and have a working knowledge of your requirements. When you’re ready to learn more, call us at Snowflake Air for your free consulation. We specialize in heat pump and mini split installation in McCall, ID and Boise Metro.