Garage Mini-Split sizing

[Rustypigeon]

I am looking at some of the Mitsubishi mini-splits that both heat and cool.

I have used a couple sizing calculators and I am getting widely varying recommendations.

Can someone tell me about what size mini-split I would need for an attached 880 sq/ft garage, 6" insulated walls, 9' ceiling with insulated attic, Located in southeast Pennsylvania.

 

[LS6 Tommy]

Depending on insualtion, I'd hazard a guess of around 1-1/2 to 2 tons for the A/C. If you're going with an inverter unit, being a little oversized is not an issue.

Tommy

 

[yeldogt]

How many windows -- doors?

The heat load may be trowing it off in PA .... have you used any type of heat in it previously (as a guide)

I have a foamed studio that's 1600 sf and I can heat and cool it with 15k ...it's all about insulation and how you use it.

 

[Rustypigeon]

How many windows -- doors?

The heat load may be trowing it off in PA .... have you used any type of heat in it previously (as a guide)

I have a foamed studio that's 1600 sf and I can heat and cool it with 15k ...it's all about insulation and how you use it.

No windows, except on the garage doors. The garage doors are insulted. There is one double-wide garage door and one single garage door. I have not used any type of heat in it previously. It is pretty well insulated with 2x6 walls and fiberglass insulation in the walls and ceiling.

I moved in the place back in February. When it was 30 degrees outside it would be 50 inside the garage. Now that it is summer it is about 95 degrees in the garage during the daytime. I am guessing it would take less energy to heat it than it would to cool it.

 

[theoldwizard1]

... attached 880 sq/ft garage, 6" insulated walls, 9' ceiling with insulated attic, Located in southeast Pennsylvania.

How much attic insulation ? 6" would be minimal, more than 12" would be better.

 

[Rustypigeon]

How much attic insulation ? 6" would be minimal, more than 12" would be better.

I would estimate that it is 6" of blown in fiberglass.