When it comes to heating and cooling your home, mini split systems are, without doubt, the best alternative to central air. However, if you’re unfamiliar with them, it can be tough to choose the right system. There are many things to consider, from choosing the right size to finding a reputable brand.
What Size Ductless Mini Split Do I Need?
Ensuring optimal comfort and energy efficiency are the most important aspects when it comes to deciding on a mini split system. However, that doesn’t always mean that bigger is better.
You’ll want to calculate the square footage of each room or zone of your home that will be served. Measure the length and width of the room and multiply the measurements to determine the square footage you’ll need to heat and cool.Consider any special circumstances, like a wall of windows or lack of insulation.
From there, you can determine the correct size in one of two ways. You can refer to a sizing chart provided by a manufacturer to determine the appropriate BTU rating for your mini split. Alternatively, you can multiply the square footage by 25 to determine the recommended BTU capacity.
Short for British Thermal Unit, BTUs usually refer to the amount of heat an appliance can generate or, as with an air conditioner, their capacity to remove heat from the air. In each instance, the question is how much energy the unit needs to generate for the air to achieve and hold the target temperature. It is crucial to make sure the components you choose work well for air conditioning for the area where you plan to use it.
How Many Square Feet Can a Mini Split Cool?
The answer to this question depends on the BTU rating of the specific mini split system. For example, a 7,000 BTU mini split can cool a room that’s about 300 to 400 square feet. On the other hand, a 48,000 BTU mini split can cool between 2,200 and 2,600 square feet of space. In general, it takes about 12,000 BTUs to cool every 500-600 square feet of space, depending on climate and the other factors we discussed. Once you know the size of your space, it’ll be easier to choose a unit.
Is it Better to Oversize or Undersize a Mini Split?
Neither situation is ideal. Wherever possible, make sure units are sized as close to correctly as possible.
When you oversize a ductless mini split system, they can short cycle. This means that they turn off and on more rapidly than they should. That, in turn, can lead to problems cooling, and they’ll be less effective at maintaining the proper humidity level. This can also raise your energy bills.
When you undersize a mini split unit, it will work much harder for longer periods of time to cool the space. This not only decreases comfort, but it also causes excessive wear and tear on the unit. On top of that, excessive run time also leads to higher energy costs.
If you can’t size the unit correctly, then it’s better to err on the size of oversizing the ductless system slightly rather than undersizing it. Discussion with a pro, on the ground, will always help.
What Makes a Mini Split DIY?
A mini split system basically involves three main parts: the outside condenser, inside mini split air handler, and the lines which connect the two, known as “line-sets”. During a typical HVAC system installation, a professional should be involved. They have specialized equipment and training that means they are qualified to work on coolant under pressure, fittings and connecting refrigerant lines correctly, which can be dangerous. They must also properly measure, vacuum, and charge the system to ensure peak performance. Each of these skills is important, and their experience and training makes their help invaluable.
Mini Split DIY kits are a very specific type of unit that comes with pre-charged line sets. This means they come straight from the factory sealed and pre-charged with refrigerant, and they can plug in relatively quick and easy, even by the homeowner. Any homeowner who feels handy and comfortable with tools and calculation will save thousands of dollars installing a DIY system.
Homeowners who have the tools on hand plus a bit of knowledge can often safely DIY this job with this specific type of system. You’ll need to be able to mount the indoor unit, run coolant lines outside to the condenser, and you’ll need to be able to mount the condenser in a safe location outside. Homeowners should thoroughly read and understand the installation manuals for DIY systems before attempting the install without a professional.
We speak to homeowners every day that have studied the installation manuals for DIY systems and feel confident in their abilities, and are excited at the savings.
Rules of Thumb for Choosing Ductless Mini Splits
- Size the unit as close to correctly as possible. Remember, you need roughly 12,000 BTUs for every 500 square feet of space.
- Shop for units that have a high SEER (seasonal energy efficiency ratio) rating. The higher the SEER rating, the more efficient a unit will be.
- Choose units with low noise levels. Mini split systems can be noisy, so shop for those with a 50 decibel rating or lower.
- Shop among reputable brands. Make sure the brand you choose has been in business for at least a few years and they have a good track record in terms of consumer satisfaction.
- Don’t forget about features. Some ductless systems come with remote controls, Wi-Fi connectivity, and more. Choose units with the features you’ll need.
Overall, mini split systems can be a great investment and alternative to a central air conditioning system, and they’ll help you keep your home comfortable throughout the year. However, make sure you choose a unit that’s the right size and has the features you need. On HVACDirect.com you will find specification sheets below each product or system, listing the relevant details and features, helping you choose the best unit. Our sizing guide can be helpful too.