Garage Ventilation

[Herm]

Whats the temp of the air coming out of the swamp cooler?

 

[edatoakrun]

...To keep the garage secure, I simply opened the attic access hatch so the hot air is push up into the attic. Any reason I shouldn't be doing this?...

Building codes often require the garage space to be firewalled from the rest of the house. This is for protection from fire, and carbon monoxide. Also, if I understand swamp coolers, you are humidifying the garage air, so that moisture will eventually be entering the attic, which you definitely don't want.

Codes? We don't need no stinking codes!

Actually Nubo makes another good point, though, in that if you have an attached garage, the swamp cooler will also provide positive pressure, tending to push the garage air (and whatever is in it) into the house, if the connecting door is poorly sealed, or left open.

Checking the code for whatever venting is required in this situation, just might not be a bad idea...

 

[smkettner]

Humidity related condensation problems in AZ summer? Really?

 

[shrink]

I installed a swamp cooler into an existing window and it is working well. It took over 24 hours to finally get the temperatures down but now it is very bearable - never getting above 90 (had been seeing up to 110 before). I had one problem with the Home Depot unit - kept tripping the GFI. Upon inspection I found they put an unprotected outlet inside the unit in the spash zone. Stupid. Pushed it back into the unit and duct taped the resulting opening closed - seems to have done the trick. Interested in feedback on my ventilation choice. To keep the garage secure, I simply opened the attic access hatch so the hot air is push up into the attic. Any reason I shouldn't be doing this? I figure pushing the attic air out the O'Hagen vents should help with the household cooling load if anything. I have fiberglass insulation in case that is a factor with sending humid air up there.

I've tried something similar, but I'm not getting nearly as good results as you. I'll go into more details on my setup later, but quick question for you, Tick Tock:

How many hours/day are you running the swamp cooler?

 

[leafkabob]

I installed a swamp cooler into an existing window and it is working well. It took over 24 hours to finally get the temperatures down but now it is very bearable - never getting above 90 (had been seeing up to 110 before). I had one problem with the Home Depot unit - kept tripping the GFI. Upon inspection I found they put an unprotected outlet inside the unit in the spash zone. Stupid. Pushed it back into the unit and duct taped the resulting opening closed - seems to have done the trick. Interested in feedback on my ventilation choice. To keep the garage secure, I simply opened the attic access hatch so the hot air is push up into the attic. Any reason I shouldn't be doing this? I figure pushing the attic air out the O'Hagen vents should help with the household cooling load if anything. I have fiberglass insulation in case that is a factor with sending humid air up there.

I had a swamp cooler on my last house. I installed "up-ducts" in a couple of rooms so that the air could vent into my attic space. Otherwise I would have had to leave a window open. I don't think you will have a problem adding some humid air to the already extremely hot dry air of your attic.

 

[TickTock]

I installed a swamp cooler into an existing window and it is working well. It took over 24 hours to finally get the temperatures down but now it is very bearable - never getting above 90 (had been seeing up to 110 before). I had one problem with the Home Depot unit - kept tripping the GFI. Upon inspection I found they put an unprotected outlet inside the unit in the spash zone. Stupid. Pushed it back into the unit and duct taped the resulting opening closed - seems to have done the trick. Interested in feedback on my ventilation choice. To keep the garage secure, I simply opened the attic access hatch so the hot air is push up into the attic. Any reason I shouldn't be doing this? I figure pushing the attic air out the O'Hagen vents should help with the household cooling load if anything. I have fiberglass insulation in case that is a factor with sending humid air up there.

I've tried something similar, but I'm not getting nearly as good results as you. I'll go into more details on my setup later, but quick question for you, Tick Tock:

How many hours/day are you running the swamp cooler?

Right now 24/7 on low. I may hook up a timer to the pump to only circulate water during the day, but since it took over 24 hours to initially cool it down, I don't want to let the heat get a toe in. The HD model I have has an electronic control that I will have to bypass - it won't turn back on if the power is cut and restored. However, the pump is connected to a switched internal outlet so it would be easy to unplug the pump and bring it's plug out to a external wall timer.

 

[Stanton]

Still getting good results from my garage floor fan (only--no other ventilation). Parked with 7TBs last night, plugged in to (delay) charge, and left with 6TBs this morning. I only charged to 80%, so I'll see what happens when I charge to 100% (which should generate more heat). It's been 100+F during the day, and my garage is <90F at night.

 

[Boomer23]

I just discovered that I already have garage cooling. We bought this house 34 years ago and it was already about 9 years old at the time. The first owner installed a cooling fan in the flat garage roof. I had plugged it in a few times over the years and it didn't activate, so I assumed that it wasn't working. Because of all of the talk about battery heating, I idly plugged it in again this week on a hot afternoon and voila, it runs. I tried it again late at night when the temp was in the 70s and it didn't run. I concluded that there must be a thermostat in the circuit somewhere. It does a pretty good job, too, cooling the garage from about 91 down to 87 degrees in a half hour or so. I haven't yet tested the thermostat on and off temps.

Now I have to decide whether the energy cost of 200 Watts to use the fan is worth while, given our moderate coastal temperatures. The hottest I've seen the garage in recent afternoons has been 93 degrees. I don't know whether temps like this versus five or six degrees cooler are really an issue for the LEAF pack or not. In addition, this fan must be 40 years old, so I hope it isn't a fire hazard. I guess if it runs smoothly and quietly, I'm golden, right?

 

[dhanson865]

Humidity related condensation problems in AZ summer? Really?

Depends on if the unit is direct or indirect.

Direct evaporative cooling (open circuit) is used to lower the temperature of air by using latent heat of evaporation, changing liquid water to water vapor. In this process, the energy in the air does not change. Warm dry air is changed to cool moist air. The heat of the outside air is used to evaporate water.

Indirect evaporative cooling (closed circuit) is similar to direct evaporative cooling, but uses some type of heat exchanger. The cooled moist air never comes in direct contact with the conditioned environment.


I'm assuming Direct evaporative would overcome even "dry" air in terms of humidity issues in an attic but then I'm just guessing.

 

[davewill]

...Now I have to decide whether the energy cost of 200 Watts to use the fan is worth while, given our moderate coastal temperatures. The hottest I've seen the garage in recent afternoons has been 93 degrees. I don't know whether temps like this versus five or six degrees cooler are really an issue for the LEAF pack or not. In addition, this fan must be 40 years old, so I hope it isn't a fire hazard. I guess if it runs smoothly and quietly, I'm golden, right?

It would be nice to put it on a timer, the sort you use for a bathroom fan. If you come home and the garage seems hot, set the timer to run for an hour or two to cool it down.

 

[Boomer23]

...Now I have to decide whether the energy cost of 200 Watts to use the fan is worth while, given our moderate coastal temperatures. The hottest I've seen the garage in recent afternoons has been 93 degrees. I don't know whether temps like this versus five or six degrees cooler are really an issue for the LEAF pack or not. In addition, this fan must be 40 years old, so I hope it isn't a fire hazard. I guess if it runs smoothly and quietly, I'm golden, right?

It would be nice to put it on a timer, the sort you use for a bathroom fan. If you come home and the garage seems hot, set the timer to run for an hour or two to cool it down.

Good idea, I might try it.

I left it running last evening and my wife unplugged it because it was noisy and she said that the plug felt hot. Looks like I need to go through that whole system and make sure that everything is up to snuff.

 

[pchilds]

The So-Cal heat wave has broke, 5 temperature this morning.

 

[TomT]

Yep, what a difference a day makes! Here is the data from my weather station (http://www.ghweather.org" onclick="window.open(this.href);return false for yesterday:

Average temperature = 74.8°F
Average humidity = 65%
Average dewpoint = 61.1°F
Maximum temperature = 87.1°F on day 21 at time 15:59
Minimum temperature = 65.0°F on day 21 at time 06:38

The So-Cal heat wave has broke, 5 temperature this morning.