Venting garage heat?

[Sacarino]

I'm thinking of installing a sidewall exhaust fan on my 20x20 attached garage to cut down on the Atlanta heat in my southeast-facing garage in the summer. My thought was to install some intake vents on two panels of the garage door and a louvered exhaust fan on the outer wall to blow the hot air. During the day, the heat alone is annoying but once you put a hot car engine in there it gets out of control. Just getting it down to the outside air temp would be a huge improvement for me, and it would certainly make the garage more pleasant to be in.

The attic above is lightly insulated (~6" of blown cellulose), and I added a reflective foil layer to the door in an effort to control the situation a bit better. All this is well and good for helping with the radiant heat from the sun but that doesn't address the car issue in the slightest.

It'd certainly be easy enough to tie a Z-wave relay into a fan (like this or one of these) and have it kick on when my temp sensor hits a threshold, but I wanted to float my idea to see if there's something I'm missing. I'd sure appreciate any thoughts or ideas you might have.

Thanks!

 

[sda]

You might look into a swamp (evap) cooler as a blower. Atlanta is too humid to run it with water, but they move a lot of air.

 

[Steve]

If you have a tank hot water heater in the garage you could also look into a hot water heat pump. It would take the hot air in the garage to heat your water then it blows out cold air. So you heat your water and get free garage air conditioning as a side effect. I am waiting on some new models to come out and I may look at it closer.

 

[TXFlatLander]

If you are using z-wave, I would think you would want to make sure it is motor control rated. Just a thought

 

[Sacarino]

You might look into a swamp (evap) cooler as a blower. Atlanta is too humid to run it with water, but they move a lot of air.

Hm... there's an interesting thought. I wonder if it would be better to use a blower to push air in and create higher pressures that escaped out via vents vs. my lower pressure exhaust idea. The upside to a blower concept is it seems like you could use the blower output as an air curtain over the interior door break. Anyone know the physics breakdown behind high vs. low pressure solutions?

If you have a tank hot water heater in the garage you could also look into a hot water heat pump. It would take the hot air in the garage to heat your water then it blows out cold air. So you heat your water and get free garage air conditioning as a side effect. I am waiting on some new models to come out and I may look at it closer.

That's also an interesting idea, but unfortunately my heater is in the mud room.

If you are using z-wave, I would think you would want to make sure it is motor control rated. Just a thought

I have a spare ZRF113, which can handle 20A and a motor up to 1HP from 24VAV all the way to 277VAC via isolated contacts. Good thought though - appreciate the sanity check.