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How to choose correct size mini split?
- Thread starter shane772
- Start date
MrBalll
Well-known member
More info needed.
We don't know what you want to cool. Just living or both living and garage.
What kind of insulation if any.
Will the door to the bedroom always be closed? In that case only the living room or the bedroom will be cooled.
What direction do the windows face and will they be covered at all?
For the living, if it has 14ft ceilings that may be tough. I have a 28 x 24 x 14. I have a 2 ton unit and it does an Ok job. I don't have a sealed garage door yet nor are my windows covered so it will do better when I get that fixed. It can however keep it down to about 85 when it's Texas hot outside. I used a calculator online and it suggested an 18k BTU unit. My installer recommended a 2 ton unit because of the ceilings. So I went with that and very glad I did.
If you want just the living space cooled then maybe a 1.5 ton unit to make up for that ceiling height. If you plan on having someone install then ask them for a suggestion since they probably install them all the time.
Kind of hard with what little info is provided. Give as much info on the building itself as you can to get actual suggestions.
We don't know what you want to cool. Just living or both living and garage.
What kind of insulation if any.
Will the door to the bedroom always be closed? In that case only the living room or the bedroom will be cooled.
What direction do the windows face and will they be covered at all?
For the living, if it has 14ft ceilings that may be tough. I have a 28 x 24 x 14. I have a 2 ton unit and it does an Ok job. I don't have a sealed garage door yet nor are my windows covered so it will do better when I get that fixed. It can however keep it down to about 85 when it's Texas hot outside. I used a calculator online and it suggested an 18k BTU unit. My installer recommended a 2 ton unit because of the ceilings. So I went with that and very glad I did.
If you want just the living space cooled then maybe a 1.5 ton unit to make up for that ceiling height. If you plan on having someone install then ask them for a suggestion since they probably install them all the time.
Kind of hard with what little info is provided. Give as much info on the building itself as you can to get actual suggestions.
I bought my Mr Slim from eComfort. They have a sizing guide
http://www.ecomfort.com/stories/1185-How-to-Properly-Size-Your-Mini-Split.html
Also, they had a free service that if you filled out a bunch of forms they would have one of their in house 'engineers' look at and give you a recommendation. I don't see the link right now - I think you may have to call them and ask about it
http://www.ecomfort.com/
http://www.ecomfort.com/stories/1185-How-to-Properly-Size-Your-Mini-Split.html
Also, they had a free service that if you filled out a bunch of forms they would have one of their in house 'engineers' look at and give you a recommendation. I don't see the link right now - I think you may have to call them and ask about it
http://www.ecomfort.com/
aunsafe2015
Well-known member
Keep in mind the sizing guide from ecomfort doesn't apply well at all for garages. For my application the sizing guide specd 6K btu when in reality 18K btu was the correct size.
What was the reason for the huge difference?
What was the reason for the huge difference?
No idea. But my garage is fully insulated with modern insulation and even has an air conditioned bedroom above the garage...so that calculator was WAY off.
It definitely doesn't hurt to upsize a mini split since they are inverter. For example my 18k btu Mitsubishi has a range of ~6k to 22k btu...so it can spool as needed. Also you need to account for opening garage doors and tall ceilings.
1 ton (12k btu) for every 400-450 Sq ft works well given ceiling height is reasonable and the garage is somewhat insulated...this is for garages. Fully insulated rooms in a house would be closer to 600-650 Sq ft per ton.
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Assuming a well constructed, insulated, good windows (not W-NW facing) space, I would not go over a 12k unit. I would suggest putting ceiling above the living space and a storage loft above that space. Why try to condition it and why not have the storage?