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or text agent green & team

Serving the Greater Miami Area


or text agent green & team


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Miami AC Tip: Sizing Ductless Air Conditioning Systems

Proper sizing of your Miami air conditioning system is one of the most important factors affecting its operation. A system that is too small won’t be able to keep up, while one that is too large can lead to short cycling and excess humidity.

This applies not just to central air conditioning systems, but also to ductless systems. The main difference is that with ductless systems, not all systems have to have air handler units installed, so you don’t need to take every room into account. To get an estimate on what size ductless system you need, follow these 4 steps:

 1.       Measure each room

To start with, you need to know the area in square feet of each room room that will be cooled by the ductless system. To do this, measure the length and width of each room. For some oddly shaped rooms, you may need to divide it up into two or more rectangles and then add the square footage of each rectangle together to get the total area of the room. Exclude closets from your calculations.

2.       Convert area to BTUs

For each room, convert the area you just calculated into how much energy will be needed to cool them, which we measure in British Thermal Units (BTUs). As a rule of thumb, multiplying square footage by 25 will yield the approximate number of BTUs needed for that space. So, a 200 square foot room needs about 5000 BTUs for proper cooling.

3.       Consider the variables

There are other factors aside from square footage that determine a particular room’s heating needs. These variables include the local climate, the number of people usually in the room at one time, the number of appliances operating in that room and how well the room is insulated. A good general rule is to add 4,000 BTUs to the total for a kitchen and 1,000 for a bathroom.

4.       Add it all up

Once you have the BTUs for each room, add them all up to find the whole house BTUs, which is generally how split systems are rated and labeled.

Keep in mind that this only yields an estimate, and that there are plenty of variables to consider when sizing an AC system. Hiring a Miami AC professional to do a load calculation is the best way to get an accurate assessment of your home’s cooling needs. Call Air On Demand today if you are interested in having a ductless system installed in your home!

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