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BigRed1500
Mar 9, 2007, 07:15 AM
The photo in the URL below is of my furnace intake / exhause. It's a 90+percent efficiency gas forced air furnace, direct vent out the sidewall of the house. The pipes are 2.5" sched 40 pvc. The one on the left is the intake, one on the right is the exhaust. As you can see, I'm having the house re-sided, and the installation of these pipes (not me, it's probably 15 years old) was done very poorly and it is unsightly. They're not level in the least, there's primer dripping all over the place, its just a mess.

Here's the question / issue: I want to dress this up and make it more clean/neat, so I want to cut the pipes off at the exterior wall to allow the siding to go on, then replace the pipes. I know that I can't replace this with a stainless "pipe in a pipe" setup because the furnace intake & exhaust pipes are on different locations of the actual unit in the basement. So I'm stuck with PVC coming out of the wall. Is there a formula that dictates the distance the exhaust must be away from the intake, or different elevations, etc (aside from the 10' from an operable window, etc)? I have to believe that there is a way to make this look better than it is now. Thanks

Snapfish: Share Photo:Registration (http://www1.snapfish.com/viewsharedphoto/p=92991173453274886/l=244628890/g=34155585/otsc=SYE/otsi=SPIC;jsessionid=8C1DAE18BCFCA45F8A879422B43F5 F92)

ballengerb1
Mar 9, 2007, 07:35 AM
Yes you can cut off both pipes to make residing easier but do not cut flush up againist the house. You need 1 in. sticking out for the new 45s. You can't reuse the same 45 degree PVCs because the old pieces of pipe are still glued inside. First lets look at you existing set up. Someone got a bit creative and added to the poor look. The final two pieces on the intake are not needed, do not replace them. One short verticle with one 45 should do it. The exhaust needs the downward 45 but not the 12 in straight piece, do not replace that. PVC isn't so bad. If you clean it with spirits you can pain it to match your new siding.

BigRed1500
Mar 9, 2007, 07:42 AM
Thanks. You say 45's, I assume you meant 90's? Otherwise a 45 would have them coming out of the wall, not hugging close to it.

Also - my guess was that the intake was brought around to keep rainwater, dirt, etc from falling in and potentially clogging it up, so I'd probably want to replicate that. So basically you're saying that they don't have to be any great distance apart, just so that the intake isn't pulling the exhaust right back in?

I agree about cleaning and painting, that was our intention once the pipes were put back in a more level configuration.

Thanks for the reply.

ballengerb1
Mar 9, 2007, 07:50 AM
Sometimes I am so dumb, yes 90s. Your house, right down to the paint,looks like mine but my pipes are about 6 inches apart. The original installer may have use the two excessive straight pieces to get the face, opening, of each pipe to be about a ft. apart. I don't know if that is code or industry practice but a foot is what I usually see. The only other suggestion to improve looks would be to run the intake straight down with a 90 and a 12 in. straight piece. Turn the exhaust immediately right with a 90 and terminate. This will keep more piping below your foundation. All of these pipes look like hell to me.

labman
Mar 9, 2007, 08:41 AM
If this project is after the heating season, I would cut the pipes off inside, and let the guy side over the holes. Then cut new ones where you need them. Just where, go by what Northern Heat says.

ballengerb1
Mar 9, 2007, 10:32 AM
Maybe I'm just being lazy but cutting inside is more difficult, you'll have to cut your own siding and without the correct tools it's a pain, you'll need to add two hubbed unions, etc... Lazy of me but I usually allow the contractor to give me a more finished product if I can. Heating season can run for another 2 months or so.

BigRed1500
Mar 9, 2007, 10:34 AM
Yeah this is happening right now, not off in the future, as you can see by the 1 missing siding panel. I like the looks of something called a "bayvent" or sidewall termination kit. I'm trying to find a supplier near me that carries them.

ballengerb1
Mar 9, 2007, 10:40 AM
When you get that info I'd be interested in seeing it. Please save my info for future sharing. Thanks

labman
Mar 9, 2007, 10:52 AM
yeah this is happening right now, not off in the future, as you can see by the 1 missing siding panel. i like the looks of something called a "bayvent" or sidewall termination kit. i'm trying to find a supplier near me that carries them.
A ready made factory unit should both look better and meet code. Instructions too. I forgot to mention that I though the existing pipes looked shabby. Somebody may have taken money for that job, but they weren't a professional.

Yikes! I just looked, it is 60 degrees out. I still am not about to start a project leaving my furnace out of service for a day or 2.

ballengerb1
Mar 9, 2007, 10:54 AM
Yep, who was that guy, Rube Goldberg? That was the ugliest group of pipes I ever saw.

BigRed1500
Mar 9, 2007, 11:36 AM
60 degrees, it's 10 here in CT now. This is strictly working on the exterior, so it shouldn't put the furnace out of commission any longer than it takes me to pop the end cap (or whatever it's really called) on.

Here's an example I found, but I have to believe there are options out there somewhere that are less expensive. $70 for a piece of injection molded PVC? C'mon!

Sidewall Flue Vent Kit for 90% Furnaces (http://www.myhvacparts.com/Catalogue/Accessories/Termination%20Kit.htm)

Scargod
Mar 9, 2007, 11:45 AM
I don't think this cover would meet the standards of this manufacturer's recommendations. I'm looking at at two-stage boiler and it says:
If the horizontal distance between the inlet and exhaust is more then 12”, increase minimum vertical separation
by the same amount. (If horizontal distance is greater then 6’, no additional vertical spacing is required).
Example, horizontal separation equal to 24” requires a minimum vertical separation of 18”+(24”-12”) =30”.
(Vertical separation is never required to be greater then 36”)
This one might be better (functionally) but it sticks out: NTI part number 82666 (York part number 1CT0303)

I don't think what you have is too out of line or that crude. I would at least wipe it down with some acetone or lacquer thinner and paint it to match the siding.
You could get creative and have the siding people cover a plywood cover plate with siding. This could hide the pipes. Include vertical and horizontal baffles in the middle and sides so the air and gasses can't directly mix behind this cover plate.

labman
Mar 9, 2007, 12:11 PM
60 degrees, it's 10 here in CT now. This is strictly working on the exterior, so it shouldn't put the furnace out of commission any longer than it takes me to pop the end cap (or whatever it's really called) on.

Here's an example I found, but I have to believe there are options out there somewhere that are less expensive. $70 for a piece of injection molded PVC? C'mon!

Sidewall Flue Vent Kit for 90% Furnaces (http://www.myhvacparts.com/Catalogue/Accessories/Termination%20Kit.htm)

It looks nice. Don't let your wife see it. You couldn't make one. For less than $10 bucks, I could make every thing is this $150 kit except the UL approved sticker, Generator InterLock Kit - Introduction (http://www.interlockkit.com/intro2.htm)

juggallojed
Mar 10, 2007, 08:19 PM
The photo in the URL below is of my furnace intake / exhause. It's a 90+percent efficiency gas forced air furnace, direct vent out the sidewall of the house. The pipes are 2.5" sched 40 pvc. The one on the left is the intake, one on the right is the exhaust. As you can see, I'm having the house re-sided, and the installation of these pipes (not me, it's probably 15 years old) was done very poorly and it is unsightly. They're not level in the least, there's primer dripping all over the place, its just a mess.

Here's the question / issue: I want to dress this up and make it more clean/neat, so I want to cut the pipes off at the exterior wall to allow the siding to go on, then replace the pipes. I know that I can't replace this with a stainless "pipe in a pipe" setup because the furnace intake & exhaust pipes are on different locations of the actual unit in the basement. So I'm stuck with PVC coming out of the wall. Is there a formula that dictates the distance the exhaust must be away from the intake, or different elevations, etc (aside from the 10' from an operable window, etc)? I have to believe that there is a way to make this look better than it is now. Thanks

[url=http://www1.snapfish.com/viewsharedphoto/p=92991173453274886/l=244628890/g=34155585/otsc=SYE/otsi=SPIC;jsessi Share Photo:Registration[/url]



I agree
Check with the local hvac supply house for a single hole penetration kit they look much better

nmwirez
Mar 10, 2007, 09:10 PM
The photo in the URL below is of my furnace intake / exhause. It's a 90+percent efficiency gas forced air furnace, direct vent out the sidewall of the house. The pipes are 2.5" sched 40 pvc. The one on the left is the intake, one on the right is the exhaust. As you can see, I'm having the house re-sided, and the installation of these pipes (not me, it's probably 15 years old) was done very poorly and it is unsightly. They're not level in the least, there's primer dripping all over the place, its just a mess.

Here's the question / issue: I want to dress this up and make it more clean/neat, so I want to cut the pipes off at the exterior wall to allow the siding to go on, then replace the pipes. I know that I can't replace this with a stainless "pipe in a pipe" setup because the furnace intake & exhaust pipes are on different locations of the actual unit in the basement. So I'm stuck with PVC coming out of the wall. Is there a formula that dictates the distance the exhaust must be away from the intake, or different elevations, etc (aside from the 10' from an operable window, etc)? I have to believe that there is a way to make this look better than it is now. Thanks

Snapfish: Share Photo:Registration (http://www1.snapfish.com/viewsharedphoto/p=92991173453274886/l=244628890/g=34155585/otsc=SYE/otsi=SPIC;jsessionid=8C1DAE18BCFCA45F8A879422B43F5 F92)
Egads Ian, who was your furnace sub. This sucks. First up there is a distance regulation between the intake and exhaust pipes. I suspect at least 4 feet. Second, what was not mentioned, for new furnaces generally there is a low voltage controlled damper that goes on to that intake piping for energy compliant efficiency requirements if done by permit.

Can the piping be accessed to cut it off from the inside and re-routed to the outside to finished duct dampers that look and work upscale? Nm

ballengerb1
Mar 11, 2007, 12:03 PM
I need to adjust my previous answer after talking with my buddy. The intake should have two 90s so it points down. The face of the intake and the exhaust should be 18 inches apart facing in opposite directions.

hvacservicetech_07
Apr 29, 2007, 01:12 AM
The intake and exhaust should be 1 foot apart the intake should have a 90 on it and the exaust should have a 45 to prevent condensation from building ice on it

BigRed1500
Apr 30, 2007, 06:47 AM
the intake and exhaust should be 1 foot apart the intake should have a 90 on it and the exaust should have a 45 to prevent condensation from building ice on it

Now I'm leaning towards using a concentric vent kit (single penetration through wall) rather than a side-by-side set up. They are aapproved for this installation, so I don't know if the 1foot distance gap still applies.

nmwirez
Apr 30, 2007, 09:51 AM
Now I'm leaning towards using a concentric vent kit (single penetration through wall) rather than a side-by-side set up. They are aapproved for this installation, so I don't know if the 1foot distance gap still applies.

Hi BigRed, Does the concentric vent kit include an air inlet low voltage damper control? Reason for the question, on the West Coast (WA, OR, CA,) inlet and exhaust control is being required for HVAC energy conservation and air quality in residential systems. Nm

BigRed1500
Apr 30, 2007, 09:54 AM
Hi BigRed, Does the concentric vent kit include an air inlet low voltage damper control? Reason for the question, on the West Coast (WA, OR, CA,) inlet and exhaust control is being required for HVAC energy conservation and air quality in residential systems. nm

No, it's strictly pipe. Pipe within a pipe, actually. Just sched 40 pvc, no dampers on this.