Condensing heater venting

Joe@buderus_2

Schedule 40 PVC pipe is approved for a "zero" clearance to combustibles for venting of the GB142. The PVC pipe can be run through an interior wall, but cannot have any joints (coupling, elbow, etc...)in the wall.
If taking combustion air from the enviroment (room) the GB142 is located in, there must be enough combustion air per code.

[Deleted User]

Condensing heater venting

Dave Yates' recent question about the Buderus GB lead me to a couple of my own on the subject of venting condensing heaters. While our Estes Park, Colorado building project is still on hold due to ill elderly in-laws who can't tolerate the elevation, final construction drawing comments are about to be addressed by our previously engaged architect. Thus this request for your expert opinions.

- Can the 3-inch PVC intake and exhaust vent pipes of a condensing heater such as the GB be run through an interior wall framed with 2x6s? There will be some plumbing runs in that wall, but plenty of extra room in the stud bays will exist. If this is an acceptable routing, I can have the architect delete a flue chase and make a main floor closet larger.

- What are the pros and cons of sealed combustion in my situation? The heater (and possibly a domestic hot water storage tank) will be the only thing in an 1,100 square foot basement mechanical room with thin slab floor. We can make that room's free vent area whatever is appropriate for the heater if this approach is better than running a 3 inch intake pipe all the way to the roof. There will be lots of other finished basement area and, due to expected rock, about half the mechanical room height will probably be less than 8 feet, so it's unlikely the mechanical room will ever be finished.

Thanks in advance for your input!

hr

Probably

the installation manual should tell you. As I recall the Weil Ultra asks for .2" inches from combustiables to the PVC vent pipe. I call it 1/2"

And .4" larger hole than the OD of the PVC pipe for going through floors. Check with Buderus for their specs.

hot rod

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[Deleted User]

I checked the GB installation manual...

which can be downloaded from this page

http://www.buderus.net/Default.aspx?tabid=47

and found nothing about clearances. Wrote to Buderus too but haven't yet received a response.

Thanks hot rod. How about sealed combustion pros/cons?

hr

I've been

installing sealed combuston products for about 12 years now. Going back to the early Weil GV golds we installed in the mountains of Utah. It makes a lot of sense in cold climate like yours, where combustion air inlets can freeeze pipes. It allows a lot more flexability in locating the boiler also.

I don't know that I have and "cons" for sealed combustion. requires two pipes, and a little more undoing to service.

I recall Buderus has excellent representation and dealers in the Denver/ Colorado area.

Did you e-mail Buderus directly for a clearence spec?

hot rod

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hr

I've been

installing sealed combuston products for about 12 years now. Going back to the early Weil GV golds we installed in the mountains of Utah. It makes a lot of sense in cold climate like yours, where combustion air inlets can freeeze pipes. It allows a lot more flexability in locating the boiler also.

I don't know that I have and "cons" for sealed combustion. requires two pipes, and a little more undoing to service.

I recall Buderus has excellent representation and dealers in the Denver/ Colorado area.

Did you e-mail Buderus directly for a clearence spec?

hot rod

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

[Deleted User]

I did email Buderus with the same question posted here, i.e. I asked about routing through the interior wall, not explicitly about clearances. I picked Harry Warren as most likely candidate from Buderus' "Contacts" page since he's identified as Technical Sales Rep. If anyone thinks there's a better contact please let me know.

You mention combustion air inlets freezing pipes. Are you referring to grilled vents sending outside air into the basement mechanical room and freezing pipes in that space? What about the sealed intake PVC vent; if run through the interior wall, might it also have such an effect on nearby plumbing runs? Or does constraining the incoming outside air to 3 inch PVC combined with the R-value of the PVC itself make that unlikely?