Can I vent horizontial out a side wall?

myselftwo · 03-01-2009, 02:05 AM

Hello,

Can I vent an 80% eff furnace out of a side wall? I'll follow the 1/4" per foot in the horizontial, then elbow once out past the wall - up four to five feet (or whatever the height requirement is) - so that the top of the "chimmeny" meets the required height above the roof.

DangerMouse · 03-01-2009, 06:11 AM

i THINK the lowest you can vent through a wall is 92% from my understanding. they make them with squirrelcage blowers to move a ton of exhaust fast. i don't think 80% would be acceptable, but what do i know? i just commented so i'd see any other answers as i'm curious now....
lots of good HVAC guys here... they should be along any time to poopoo me and give you a better answer. lol

DM

Plumber101 · 03-01-2009, 09:18 AM

Depending on your code but most will allow to come out a side wall and then go verticle to provide proper draft.

It would be wise to check with your local codes department.

I would say yes but not terminate at a horz.

yuri · 03-01-2009, 09:52 AM

You can have a external B vent chimney but it must be supported properly and encased and done by a professional chimney co. to code. Most people don't as it is expensive and ugly. If the furnace is getting older it may be more cost effective to go with a high efficiency furnace and use plastic venting.

kenmac · 03-01-2009, 06:43 PM

Don't know if it's same in every area. Where I am . If you go outside & up the side of the house with B vent. A insulated chase must be installed around the B vent

tk03 · 03-01-2009, 09:32 PM

The use of "B" vent outside the structure is not allowed by the "B" vent manufacturers unless insulated and boxed in.
Check with the furnace manufacturer to see the venting options. They have the only say in venting if not a class 1 appliance(chimney vented).