Monday, September 02, 2024

Building A Whole-Garage Fan

 ... when you're lazy and your ladder is too short.

In the desert, not only can you not remember your name (IYKYK), you also experience wild swings in temperature throughout a 24-hour period. With no cloud cover, days are hot and nights are cold. Your garage stores that heat during the day and then acts as a radiator throughout the night, making your AC run harder.

I've always loved the idea of having a whole-house fan, which draws in cool evening air from downstairs and displaces hot, attic air, but the geometry of our upstairs attic and ceilings won't permit one. Our garage, however, is a different breed of cat. We have a pair of operable skylights in the garage which would work nicely as a cooling system if I just put a big fan in one or both of them. The garage roof slopes down from the roof of our second story, so those skylights are a good 20' off the ground. No problem, right?

I bought an inexpensive, big fan with plans to build a simple, wooden frame for it, mount it in one of the skylights and power it from the lines that feed the garage lights and door opener. I got my brand-new extension ladder down from its mount on the wall, extended it all the way and ... it was too short to reach the frame of the skylights.

Doh!

I hadn't thought about measuring the distance up to the skylights when I bought the thing, so I got the medium-sized one which seemed large enough. Hmm. What to do?

After pondering renting a cherry picker or some such hoist, it dawned on me that it didn't matter where the fan was so long as cool air was drawn into the garage. My first experiment turned out to be the only one I needed. I cracked the garage door open about 15", placed the fan in front of the gap and turned it on once the outdoor air had cooled. Voila! I had a whole-garage fan!

I recently bought one more SensorPush temperature and humidity sensor and placed it on the side yard in perpetual shade. Here's what it read during my experiment.

You'll probably need to click on the image to get a good look at it.

You can see the knee in the curve at the far right hand side. That corresponds to the activation of the fan. It worked like a charm.

Right now, the system is still manual. Whenever I want to turn it on, I need to crack open the garage door and put the fan in the right place. I don't have any vents into the garage on the ground level, so unless I cut up the walls, I can't make it automatic. The other downside is that with the garage door open like that, snakes can get into the garage, something they've done in the past.

Anywho, I now have a whole-garage fan, albeit a clumsy, manual one.

2 comments:

tim eisele said...

If you are willing to punch a hole in the wall of your garage, I recommend something like one of these:

https://www.amazon.com/iLIVING-Shutter-Thermospeed-controller-ILG8SF12V-ST/dp/B08FF9Q5JH?source=ps-sl-shoppingads-lpcontext&ref_=fplfs&smid=ATVPDKIKX0DER&th=1

We had one in our milking parlor when I was a kid, and it made a huge, huge difference. The big deal of having it built in is that it is a duct matched to the fan, so the fan actually blows air through the hole instead of mostly just swirling it around inside the room. And the louvers outside make sure that the rain doesn't get in when the fan isn't running.

If it actually got hot here more of the time, I'd probably spend more time and effort setting up an automated cooling fan system. I mainly want something that would turn on as soon as it was cooler outside than inside, and then ventilate like crazy until either the inside of the house hit the target temparature, or the air outside got hotter than inside. As it is, we only really need one for a couple of weeks a year, so right about the time I get hot enough to consider doing something about it, the time has passed and I forget about it until next year.

Mostly Nothing said...

I don't think you need to fan directly in front of the garage door. Couldn't it be mounted in the ceiling exhausting toward the sky lights? How much does the garage door seal? Air is still going exhausted and will have to be pulled in around the door.
Some sort of vent would help, of course.
Since we moved to our new house, it has annoyed me that the big double gate was just nailed shut. I wanted that gate to work. Even though the raspberry bushes, block most access. This weekend, I pulled the old rotten wood down, and got new pressure treated wood. It turned out pretty well. Though one of the posts doesn't seem to be anchored in the ground quite right.
A bird also flew into the garage, It took hours to get it out dumb thing kept trying to fly high to get out. Finally, got it darkened enough, and the 2 of us chased it to the service door.