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Posted By: MtnHiker Attic Fan Question - 06/15/21
So I noticed my attic fan that vents hot attic air out through the rooftop did not seem to be running. Been dreading going up there for a week. Assembled all the tools suited up head to toe with resperator and crawled up there today at 6:30am. Bent over at the waist about 3 feet to work in while stepping across and balancing on the ceiling joists under 18" of rock wool. Good news no foot thru the ceiling today. Set attic thermastadt to lowest seting no go on fan. Checked voltage and have power. By passed thermastadt wire direct to fan still no love. Son of a bitch. Totally disconected hand spinning fan it has some drag so its toast. No way to pull just motor from attic side. The way it is assembled i have to remove big sheet metal screws from the roof and attic side to get it out. I installed it +- 15 years ago. Home Depot unit. Can't remember if the mount was one or two pieces. Hoping it is two piece and a new one can slip into the old round sheet metal mount otherwise I gotta rip shingles tear it off and re tar and shingle basically about the same amount of work that I did installing when I was in my 40s. Did I mention it ws 103 in SLC yesterday. It pisses me off but I may hire somebody because I just don't want to deal with it.

Question there is a lighted switch in the hallway. When it is in off postion it is reading 88 volts at the fan. It reads 120 when on. That seems like a pretty high phantom voltage. I wonder if that problem is in the switch or if it the could be running paralel to a live wire or is there a ground issue?


This is old 3 wire(black, white, bare copper) white sheath romex. Maybe a 30 foot run unforteneately under insulation so I cant see it. It was servicing a swamp cooler origionally and I repurposed it and swapped the hallway swamp control switch for a lighted rocker switch. It has run fine for +-15 summers but may have always had this phantom voltage. (which if attic went above 110 temp could have fed that to the fan and maybe toasted the motor )

I have not looked at my breaker pannel yet to see if it is on its own cicut and the feed is grounded. Will do that tommorow.

I have plenty of yellow 12/2 so I may swap the switch and run new romex for the next unit. The gift that keeps giving.
Posted By: Stickfight Re: Attic Fan Question - 06/15/21
That reads like a Chicago 3 way. What else is on the circuit?

I’d be replacing the whole thing with a static vent. Powered roof fans generally cost more to run than they save, and you probably don’t need to force to a certain number of air changes.
Posted By: las Re: Attic Fan Question - 06/15/21
Guy that wrote "Rich Man, Poor Man" had it right. Houses are a liability, not an asset.

Between "remodeling", needed maintenance (staining and painting) and an in-progress deck add-on and hot tub, we are into ours for over 40 K since January. Not done, yet either... Hot tube goes in next week I think, then the deck contractor has to come back for the framing and Lexan install overhead.

Next year the 35 year shingles get replaced. Hope like hell no other roof stuff, underneath. And I need a shed-roof add-on involving a 40', 8 foot concrete retaining wall to the garage to park some toys under during off-seasons, winter and summer.

I ain't doing either. Even a 4/12 pitch asphalt shingled roof two levels up is no place for a 73 year old (that's my story and I'm sticking to it, by damn!). Besides, I'm slow. Roofing needs a crew, IMO.

Oh, sure, I'll go up and push snow off, but that's a "soft" landing.... smile
Posted By: Beaglemaster Re: Attic Fan Question - 06/15/21
I'll second the static vent idea, especially with 18 inches of insulation. Powered attic fans were popular around here years ago but you don't see them much anymore. Anytime I can replace a moving part with a nonmoving part I consider it a win. Hire a roofer.
Posted By: RockyRaab Re: Attic Fan Question - 06/15/21
Look at a solar attic fan. Runs when the sun is up, stops at night (no noise) and uses no house current. Ours may have just died after eight years and if so, I'm going to hire somebody to replace it. It can all be done from on top, so no wading through blown-in stuff in the attic. At my age, I'm not going up there.
Posted By: kappa8 Re: Attic Fan Question - 06/15/21
Originally Posted by Beaglemaster
I'll second the static vent idea, especially with 18 inches of insulation. Powered attic fans were popular around here years ago but you don't see them much anymore. Anytime I can replace a moving part with a nonmoving part I consider it a win.


Bought my first Michigan house in 1987, which was built in 1953. Looong before central air conditioners. Had an attic fan. Even though we paid for central air installation, wife was smarter than to burn $$$. She'd fire up the ceiling fan at 6:00 in morning for 15-20 minutes. Drew in all the cool, night air and instantly dropped the house 5 or more degrees. A/C wouldn't kick on until 10:00 or 11:00 when outside temps starting kicking in.

Just bought another 1960's built house for kids. Didn't have whole house attic fan, so bought one at auction. They. Are. Great!
Posted By: MtnHiker Re: Attic Fan Question - 06/15/21

Stickfight

Will look at circut tommorow. Dont know if it is on a dedicated circut. Once i flip the right breaker I can pull the hall switch and and see if it is one in and out or other and test the wires too and from the switch and see if there is any power that should not be there coming from the wire to the attic. Unfortuneately all wire in the attic is burried under rock wool. As for static vs powered I am not sure here. We have tremendous sun loads and my instict is this was a worthwile use of electricity to cool atic reducing cooling load in house and keeping shingles cooler but I may be wrong. However this is and older building and it has inndequate venting. There are 3 small gable vents , no soffit vents and no roof vents so I installed the fan to mitigate. So if I installed several vents that would probably be better but it would cost alot because most of that soffit work is second story.

Las

A yurt is souding good right now! Already replaced the main floor Furnace/AC/Hummidifier this year for $10K. The lower level furnace AC is 10 years old so.....

Couple plumbing issues to deal with. And i bet my shingles are long in the tooth.
Posted By: MtnHiker Re: Attic Fan Question - 06/15/21
Kappa8


I think you are talking about a different thing. My fan is at the roof and pushes air out of the attic and sucks air in the attic gables. It is isolated from the lower living space. Mine is not ceiling mounted i know whay you mean though and those are good at night during the right conditions.

I
Posted By: MtnHiker Re: Attic Fan Question - 06/15/21
Rocky


Having 3 of those solar vents installed may be the best idea yet! My building is T shaped with 3 gable vents. Thanks for that idea.
Posted By: RockyRaab Re: Attic Fan Question - 06/15/21
Yup, they're perfect for Utah. I just capped off the wires to the original AC fan and labeled the hall switch as disconnected. It (and the attic thermostat) are there in the event I may someday want to go back to a 120v fan - but I doubt I will. The solar one just flat works.

BTW, I also installed a 120v bathroom vent in my garage ceiling wired through a thermostat. When the garage tops 90 degrees, the fan comes on and pulls air from an opened window on the north shady side. Cools the garage pretty well.
Posted By: simonkenton7 Re: Attic Fan Question - 06/15/21
The ridge vent is the best form of attic ventilation. Makes no noise, uses no electricity. Can't break.
Posted By: slumlord Re: Attic Fan Question - 06/15/21
Not reading War And Peace

Sometimes you can just beat on them first time of the warm season and it will get them going.
Posted By: MtnHiker Re: Attic Fan Question - 06/15/21
Slum,

I am honored to be compared to Tolstoy. 🤣🤣

Yeah i spun it and smacked with a crescent wrench (did not have a hammer). Just left that chapter out.

What else could you have to do than read my fascinating post descring the suffering us old dudes go through to keep our castles comfy for the wife?

😁
Posted By: Whiptail Re: Attic Fan Question - 06/15/21
Originally Posted by simonkenton7
The ridge vent is the best form of attic ventilation. Makes no noise, uses no electricity. Can't break.


Can't disagree too much with this one though a friend's parent's leaked in a hurricane in Houston. The wind blew the water up the roof and into the attic.

My attic is significantly cooler with the ridge vent.
Maybe in a colder climate you might want to shut it off in winter?
Posted By: wabigoon Re: Attic Fan Question - 06/15/21
Yup, I'll go along with the ridge vent.
Posted By: kenjs1 Re: Attic Fan Question - 06/15/21
Originally Posted by simonkenton7
The ridge vent is the best form of attic ventilation. Makes no noise, uses no electricity. Can't break.


I lean that way too after deliberation. Checking your soffit vents is worth a look as well. I took off my vent covers and found basically a single hammer swing hole and debris that was hidden by the vent cover. In other words almost no intake. I opened these up with a key hole saw and that sweat equity paid off for me.

Posted By: AZmark Re: Attic Fan Question - 06/15/21
Without being able to see the install and troubleshoot its hard to say. But if your reading 88vac then it sounds like you've got a open neutral somewhere in the circuit. And yes, if youve fed 88 vac to the fan it likely burnt the winding. Low voltage=higher current and then overheats the winding, sometimes without the motor even turning.
Posted By: JeffyD Re: Attic Fan Question - 06/15/21
When I was fire chief, we had a house fire that set off the thermostat controlled attic fan. Sent the flames from one end of the attic to the other.
Single digit temps that day, had to keep the trucks in rotation back to the station, to prevent the pumps from freezing up. Had two guys slightly injured when they fell through the ceiling.
Still, managed to save the first floor, and the house was soon rebuilt.

Shortly after, when I had my roof re-done, I had a ridge vent installed.
Posted By: wabigoon Re: Attic Fan Question - 06/16/21
The regular roof vents work as well.
Posted By: kenjs1 Re: Attic Fan Question - 06/17/21
Originally Posted by JeffyD
When I was fire chief, we had a house fire that set off the thermostat controlled attic fan. Sent the flames from one end of the attic to the other.
Single digit temps that day, had to keep the trucks in rotation back to the station, to prevent the pumps from freezing up. Had two guys slightly injured when they fell through the ceiling.
Still, managed to save the first floor, and the house was soon rebuilt.

Shortly after, when I had my roof re-done, I had a ridge vent installed.



WOW- thanks for that bit JeffyD. Never occurred to me but- heck yes I see it happening. My take on the solar powered ones were how do you know if the are still working without actually checking them and how many folks would go a year or more between checks- and how easy is it to get to them to check? Then the cost was hundreds a piece to have replaced if I am not mistaken. In other words never pay for themselves.
Posted By: Oldman03 Re: Attic Fan Question - 06/17/21
Yall had me going for a while. Kept trying to figure out what kind of attic fan was being discussed. Finally figured out vent fans was the subject.

Down here, in the Far Northern Parishes of Louisiana, an attic fan is a 3'-4' fan mounted in the ceiling, around the center of the house. It blows upward and is used to draw cool air thru the windows of the house.
Posted By: cumminscowboy Re: Attic Fan Question - 06/17/21
Your house should not need an attic fan in the summer. The winter is actually when you more likely need it. If that. I have an exhaust fan though it’s belt driven sucks air from inside the house vents out the attic
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