Hot wall in house, what to do?

[Nick1994]

Wall was cold this early morning after the attic cooled off overnight. Switching the breakers to turn off power to bedrooms was unsuccessful. The breakers labeled as bedrooms didn't turn them off, and I didn't want to flip breakers on the apartment where my brother lives.

My grandfather says some guy he knew built the return air system years back and built it out of wood, I believe it has gaps and cracks in it and is sucking air in from the wall from the attic. I'll look in the air return box with a flashlight and see what it looks like.

 

[another Todd]

Originally Posted By: Nick1994
Wall was cold this early morning after the attic cooled off overnight. Switching the breakers to turn off power to bedrooms was unsuccessful. The breakers labeled as bedrooms didn't turn them off, and I didn't want to flip breakers on the apartment where my brother lives.

My grandfather says some guy he knew built the return air system years back and built it out of wood, I believe it has gaps and cracks in it and is sucking air in from the wall from the attic. I'll look in the air return box with a flashlight and see what it looks like.


I think you will find your problem following this strategy.

 

[sleddriver]

Originally Posted By: Nick1994
My grandfather says some guy he knew built the return air system years back and built it out of wood, I believe it has gaps and cracks in it and is sucking air in from the wall from the attic. I'll look in the air return box with a flashlight and see what it looks like.
Good idea. You may want to vac it out with a shopvac before crawling in there.

Your evaporator core is also going to need a thorough cleaning!

 

[Pop_Rivit]

Originally Posted By: Nick1994

I'm wondering if it's hot air from the attic getting in there? It was 114 today, attic is like 180 degrees. With the air return at the bottom there maybe it has a leak and the auction from it is pulling down the hot attic air through the holes that are drilled for the electrical wires?


Your attic should not be that much warmer than the outside air temperature. You have some significant heat pressure on the interior of the house from poor design, poor insulation, poor ventilation, poor HVAC or a combination of some/all of them.

While it shouldn't be too hard to determine if the attic heat is the issue with the wall, getting it sealed up is only masking a bigger problem.

 

[Nick1994]

This is Phoenix, the hottest city in the U.S. It doesn't surprise me with how hot the attic gets.

One of the wind turbines on the roof isn't spinning so well, and I'll replace it maybe this weekend.

Here's 3 websites that say it can get 160-180+ degrees easily in the attic

https://www.precisionairandheating.com/home-performance/attic-ventilation/

http://www.lyonsroofing.com/blog/whats-the-best-way-to-ventilate-an-attic-in-arizona/

http://www.greenbuildingtalk.com/Forums/tabid/53/aff/16/aft/80906/afv/topic/Default.aspx

 

[SHOZ]

I had a new roof put on and they installed ridge ventilation. Took out three turbines when the did it. I could tell from the smell of hot insulation coming out the gable vents it was not doing the job. Went up there last fall and I could see the resin being driven out of the 60 year old 2x4s. So I ripped the ridge vent out and put in three more turbines.

When using the turbines be sure t get all aluminum ones. They spin much easier than the steel ones. I had one new aluminum one and bought two more that I though were aluminum till I opened the box. They are steel turbines with an aluminum base. They don't spin near as good.

I also put n a temp display with remote lead up there. It usually runs 20F-40F higher than ambient.

 

[Nick1994]

It's attic air getting into the air return. Here's some pictures of the return. The inner wall paneling is being sucked in, after all these years (40+ since it was put in) the nails pulled out and it's sucking in attic air. The left side has a piece of drywall hanging down, looks like it was up in the studs blocking air or something and has fallen down. I don't know yet how we'll fix it. There's a board at the bottom of the closet I might be able to pull up to be able to get access.

I also installed 2 new Whirlybirds, they spin MUCH better now!

Thanks everyone for your help!

 

[another Todd]

Expanding foam should seal it up. At the top as well as the bottom, sealing both ends of that channel.

 

[Nick1994]

Originally Posted By: another Todd
Expanding foam should seal it up. At the top as well as the bottom, sealing both ends of that channel.
That's what I was thinking, the problem is there's no way to reach it, that board sticking out is a good 6 feet away (I zoomed in). So somehow the floor of the closet above it is going to have to come out, and there's another raised closet in the hot bedroom that's above this air return (also above this board sticking out). And since I'm in there, I'll probably just replace the wood and screw it in and seal it up real good.

Then this winter we'll get up into the attic and make sure it's all sealed up where the electrical wires go through the 2x4's. Probably with expandable foam.

 

[sleddriver]

Wow...that's a mess. To seal that up right, you're going to have to remove the elevated closet floors for sure. Foam alone won't work. I'd suggest cutting sheetrock or 1/4" ply to cover the side open framing areas, then seal it all around the edges with caulk or mastic.

Then REALLY get the evap coil cleaned!

Re: Roof. Looks like a hip. For any roof ventilation to work, it needs sufficient air intake at the soffits. Plus, they need to be free of any blown-in insulation.

I had to enlarge all of mine + cut in new ones to properly flow a ridge vent. My attic temp is about 10°F above outdoor ambient, according to a remote temp sensor I installed up there decades ago.

Dark brown/red shingles in your climate???