Oil Boiler vent pipe code

[waynesoper]

I am having trouble finding a code that prohibits instalation of an exhaust vent pipe underground. I do not know thge material used. But it is a modification of the original typical system.

I know it's got to be wrong but I needd ze papers

Thanks, Wayne

[Kyle Kubs]

Wayne, it would help if you would elaborate a bit about what kind of system it is.

Venting underground to where? Is this a downfire burner?

What kind of boiler, how old?

Pictures?

The only material I know of that you may be talking about would be Transite pipe. Asbestos/cement composite.

To my knowledge there is no such specific code.

[waynesoper]

Oil fired boiler 20 + yrs

Vent originally to interior chimney wall at basement center.

Someone wanted a large family room.

Boiler room got smaller and vent would have run across the shelving unless put behind and they didn't want that.

Vent was sent out directly behind the boiler under the basemnent window underground about 24 inches then turning right towards the rear of the home and chimney and then I presume inderted into the chimney through the side. all still underground.

I don't know what they used as the only visble is the single wall pipe going out through the block wall.

Code states must exit the home to the atmosphere which puts the Kiebash on it but is there something else out there that would have permitted it.

This is a well built and renovated 2 mil home. Not some hillbilly abode. I can't see that the town would have missed it but. Sorry no pics. Took 100 and missed that one, my stupid!

[Kyle Kubs]

Sounds ridiculous. It's going through the foundation wall, outside then coming back to the chimney?

So if I understand what you are saying, some codes you might look at would be;

Flu connector is required to be as short as possible and direct to the chimney. Sounds like it has enough bends in it to violate the maximum length of a flu connector just by the equivalent length of the bends.

Pitch requirements

Was there room for a barometric damper which is required.

I'm sure there are others.

Don't take this wrong but, are you sure you're seeing what you're seeing? What you are explaining sounds totally absurd.

[Jim Katen]

I am having trouble finding a code that prohibits instalation of an exhaust vent pipe underground. I do not know thge material used. But it is a modification of the original typical system.

I know it's got to be wrong but I needd ze papers

Thanks, Wayne

Page through the IRC, Section M1803. There are a bunch of things that might apply limitations to the installation you're describing though I doubt you'll find anything that prohibits it outright.

I saw something similar once. It was a house from the '20s. The oil furnace vented straight out through the foundation wall and ran underground for about 5' till it joined the chimney. It was a straight-arrow run in terra cotta flue liners that were set horizontally in the soil. Very creative. The only problem was that the underground section must have condensed like crazy because the flue liners had completely deteriorated & collapsed. I discovered this using my keen powers of detection when I fired the furnace and the room filled with oil smoke. When I removed the vent connector from the thimble in the foundation wall, all we could see was terra cotta rubble & soil. The path to the chimney was completely blocked.

The company that came out to repair it excavated the tunnel and installed a new stainless vent connector -- still underground.

[waynesoper]

Yeah, This one had great draft but can't see the condition of the liner and as much as I wanted to pull the vent apart, I didn't, and told them to pay the chimney specialist to do a full inspection.

[Jim Morrison]

Said Katen: "I saw something similar once. It was a house from the '20s. The oil furnace vented straight out through the foundation wall and ran underground for about 5' till it joined the chimney. It was a straight-arrow run in terra cotta flue liners that were set horizontally in the soil. Very creative. The only problem was that the underground section must have condensed like crazy because the flue liners had completely deteriorated & collapsed. I discovered this using my keen powers of detection when I fired the furnace and the room filled with oil smoke. When I removed the vent connector from the thimble in the foundation wall, all we could see was terra cotta rubble & soil. The path to the chimney was completely blocked."

I've seen roughly that same setup about a half dozen times. You should tell your client to have a heating guy check it out. It's hard to believe it could be working properly.