mini-split system

How to Size Your Ductless Mini-Split System

July 13, 2021

Looking for a more efficient, faster way to cool your home? A ductless mini-split system could be exactly what you need. However, before you decide to invest, you'll need to know a few things, including how to size the system correctly.


What Are Ductless Mini-Split Systems?


First, let's address what we mean by ductless mini-split systems and how these differ from central heating and cooling systems. Like central HVAC systems, ductless mini-split systems can heat and cool your home.


However, unlike those systems, these do not require any ductwork connecting the rooms in your home. Instead of one large system connected by ducts, you'll have a network of smaller ductless mini-split units, each designed to cool the space in which it's installed.


Why Consider a Mini-Split System?


Why go this route rather than a more conventional central HVAC system? You'll find several reasons, including the following:

  • Improved energy efficiency
  • The ability to create a "zone" heating/cooling strategy
  • Improved heating and cooling of your most-used spaces
  • Improved flexibility in home design and space utilization

Why Is Sizing Important?


While a ductless mini-split system is more efficient than other heating and cooling options on the market today, size is a critical consideration. If the system is too small, it will waste energy trying to continuously heat or cool your space. If the system is too large, it will suffer from short cycling and will fail prematurely.


Given how important sizing is, how do you make sure that you get the right-sized system for your needs?


First, get used to the different terminology. Most central air systems are measured in tons – the amount of heat that a unit can remove from your space in one hour. However, ductless mini-split systems are measured in BTUs, or British thermal units, because they don't heat or cool the entire home, just one part of it.


How Mini-Split Systems are Measured


The first thing you'll need to do is measure the space to be heated or cooled. Measure each room where you intend to install a mini-split unit so you can get the right size. To get the square footage, measure the room's length and width and then multiply them together. So, a room that is 15' x 15' would be 225 square feet. With that measurement, you can start considering your options for units based on their BTU rating. Here's a quick breakdown to follow:


  • Up to 250 square feet: 6,000 BTUs
  • 250 – 300 square feet: 7,000 BTUs
  • 300 – 350 square feet: 8,000 BTUs
  • 350 – 400 square feet: 9,000 BTUs
  • 400 – 450 square feet: 10,000 BTUs
  • 450 – 550 square feet: 12,000 BTUs
  • 550 – 700 square feet: 14,000 BTUs
  • 700 – 1,000 square feet: 18,000 BTUs
  • 1,000 – 1,200 square feet: 21,000 BTUs
  • 1,200 to 1,400 square feet: 23,000 BTUs

In addition to square footage, you also need to consider other factors. For instance, if you have poor installation, you'll need more power to compensate. If you live in a hot climate, you'll also need more power to compensate.


With the right-sized ductless mini-split system, you can enjoy efficient heating and cooling. You can also benefit from a zoned climate control strategy that improves your comfort while reducing your energy usage and your demand for natural resources.


Are you looking to work with an experienced team of HVAC Technicians ? Call Home Mechanics for your heating, cooling, plumbing, and electrical needs or email us directly at [email protected]. We are always ready to provide you with the best HVAC solutions.

Feel free to reach out. We’d be happy to help!

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Why call Home Mechanics?

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Whether you require simply deplete cleaning or a whole pipes registration.

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate.

Whether you require simply deplete cleaning or a whole pipes registration.

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate.

Whether you require simply deplete cleaning or a whole pipes registration.

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