When I bought this house (30 years old) both my inspector and I failed to catch that the basement bathroom had an exhaust fan which simply vented into the adjacent furnace room. That part of the house is fully below grade. Now that I’m replacing the furnace with a new condensing furnace which uses PVC to vent outdoors I can fix this problem. Thought is to run an additional 3″ PVC pipe, do a 90 degree elbow and come up to slightly above grade level. Question is, how do I cap this pipe, both to keep out bugs and other creatures and to keep out rain? Also, this will come out near a goround floor window and the A/C compressor. How far should I stay from each of those?
Replies
Put on a screened flapper. Unless you are stinky, don't worry about the window. The only issue with the AC unit is that it doesn't block the vent. There are zero issues with the functionality of the AC.
You can buy the wall outlet vent cap thingy at any ordinary building supply place, HD, etc. It'll consist of an angled hood to keep the rain out, a flapper that closes by gravity when the fan is off, and a screen for the bugs. Code will require some distance between the outlet and the window, check with your local building dep't for the right number in your area. Here I think it's 3 ft, but could be wrong.
-- J.S.
I'm aware of the wall caps, that's not the problem. The problem is that given where I'm going to be coming out of the house (a confined space shared with two 4" PVC pipes providing make up and exhaust air for my furnace) and that I will be exiting the house underground, I will actually end up with a vertical PVC pipe sticking out of the ground. Thus the standard wall cap is going to require another 90 degree bend and look somewhat silly.
In that case, maybe the kind of cap used on vertical pipes on the roof would be the way to go. Rig a screen inside to keep the bugs out.
-- J.S.
Im just wondering, is your yard grade above your basement walls?
Gooseneck the pipe(s.)
edited to add:use 2 @ 90's to make a goose neck that has the opening on the bottom.
SamT
Edited 5/25/2003 6:41:01 PM ET by SamT
I don't know if I'd join my bath fan to the furnace exhaust. If something goes wrong you could be pumping nasties back into the house. Odorless, colorless, you'd never know.
Spring for the extra pipe and vent them seperately.
I was talking to a homeowner who has one of these high efficiency furnaces installed, he said it didn't keep his house as warm as he would have liked on the really cold days in Canada.
Turtleneck
Trust me, the furnace and the fan won't share any pipiing. My issue is more on how to make this look acceptable from the outside of the house, along with minor concerns about being too close to the A/C compressor -- don't want the air circulation from that constantly pulling air from inside the house. And in response to a previous post, yes, this pipe will exit the house underground.
Trust me, the furnace and the fan won't share any pipiing. My issue is more on how to make this look acceptable from the outside of the house, along with minor concerns about being too close to the A/C compressor -- don't want the air circulation from that constantly pulling air from inside the house. And in response to a previous post, yes, this pipe will exit the house underground.
My apologies for not understanding you before replying
I'd run the pipes out of the ground and add a 90º capped with a screen. The AC unit shouldn't pull from the pipes. I don't think it could lower the pressure at the pipe. A slight Venturi effect could occur from a strong wind but thats normal. Turtleneck
I'm sure you can buy an exhaust stack cover similar to those used on gas fireplaces (B vents ) they are around 4" but are usually a galvanized affair that I'm sure could be painted some inconspicuos color.. as far as the air conditioner...no worries.. the screen deals with the bugs and if there are no snow issues no problem either, the only thing left is condensation when the warm moist bathroom air hits the cooler night or winter air(if applicable) and condenses the rund back down to your fan..that would be my concern.I've always tried to slope vents (as soon as possible) downward to run as much condensation away from the unit as possible.This may not be an issue here but thought I'd point it out as a possible prob. to think about.Cheers, Larry