How much AC/Heat do I need?

[bigdubz]

I have a small two car garage, 19x21 with 7.5ft ceilings. It has no windows, two 8 foot doors(wood slab type), and sits under the master bedroom which is insulated and conditioned year round.

Once I finish insulating the two exterior side walls and sealing up the doors as best I can, what kind of BTU range should I be looking for?

Due to HOA restrictions, I'm thinking of going with a portable ac unit that can be vented through a 4 inch dryer vent installed next to my actual dryer vent. Anything more obvious outside like mini-split or "window unit mounted inside"-vent would probably not work. For heat, I think a smaller electric heater (5k watts) would work, and I'll have a 60amp sub-panel installed to power all of it.

I was thinking 12-15k for cooling, ideas?
thanks,
Andrew

 

[lzenglish]

I'm just curious about your home owner assoc. restrictions, what are they? You could hide a little mini split condensing unit just about anywhere that has free air access, as they are the size of a small suitcase. As far as sizing your unit, you need to do a heat load calculation (short form will do), on the garage. If you do decide to go with a portable spot cooler, keep in mind you will still need to deal with the condensation it will produce. I'm sure you will want to hard pipe it, with a small ejector pump, so you don't need to mess with emptying the condensation on a daily basis. Good Luck!


Wayne

 

[Jackfre]

The answer will vary depending upon where you live. Manitoba or Miami? Do not oversize your cooling. You will end up with a clod, clammy, wet space. I would do a 9k mini-split heat pump.

 

[bigdubz]

Thanks for the responses.

I live 15 miles northwest of Washington D.C. We got some upper 90's days, but generally I'm looking to manage the 85-95 days where the humidity stays at 80-90% all day. I'll google the short form load calc and see what that says.

I will certainly plumb a hard line for the condensation. Another consideration for the portable is that I can use it elsewhere in the house to spot cool if needed. My wife is 4 months along with our third, so it would be nice to use it as a supplement during a hot streak.

The HOA... how can I convey this... I'm not allowed to park a pick-up truck outside my house. The crazies even came to measure my Yukon XL a few weeks after we moved in. I had to bring up the GM website to prove that it fit within the size restrictions they have.

Even in the people's republic of Maryland, this HOA is an extreme.

What can I say, the opportunity to buy a foreclosure for a song was too good to pass up. It is a nice neighborhood otherwise, great neighbors and schools. I've lived in this county my whole life, so I guess I'm used to it...