Venting a condensing boiler

rumn8r

My house is 38 years old with lots of concrete, brick and glass. If I go with a condensing boiler the best option is to run the vent through unheated underground space for ~6 feet (a pipe tunnel) and then up through a concrete ceiling, up the outside of the house for ~12 feet, through an overhang and out the roof (~ 4 feet from the edge of the roof). I don't see any information in any of the technical literature of the major mod con manufacturers that covers this situation. Is this acceptable? How much vent insulation is needed? What is used to insulate? The vent will probably still be colder than if run through heated space; is this OK?

Ken_40

Dig deeper...

All manufacturer's have installation and venting parameters stated. The develeoped length (runs and a multiplier factor for elbows) must be in comliance or "issues" will follow; one of them potentially resulting in a very cold home or worse.

Pitch, in your scenario, would be a prime factor.

Dig deeper into the websites or manufacturer's literature. You'll find exactly the answer you need.

Floyd

Have done it...

log home... owner didn't want no steam anywhere close to the house. Ran the 3" PVC under ground 40' to center turnaround in drive way, no insulation but make sure you pitch back towards the house.. Looks pretty cool when you drive in there in the winter... steam rising from behind some bushes...
Has worked just fine for four yrs. now....

Floyd

rumn8r

Floyd

OK, that opens up other possibilities because the pipes can be run out the basement utility room underground about 25 feet to a masonry 3 sided utility enclosure (air conditioning condensers, gas meter, electric meter). It would involve excavation but no new masonry. Why didn't you insulate the underground pipes?

rumn8r

STOP!!!

Read the manufacturers instructions as Ken pointed out.

The utility companys don't want your vent termination within 10' of their equipment. And there IS a good reason...

Consider having a lawn ornament company build you a large lion with the vent coming out of the lions mouth/nose with the vent pipe internal to the structure of th elion. Think outside of the box. Enjoy the condensation. You will be living with it for the rest of the houses life...

Someone has a picture of a Griffin that someone installled at the roof line of their house with the vent running out of it. Looks pretty neat.

ME