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Flue piping

Firedragon_4 Member Posts: 1,436
General Electric furnace.
If it's original, it must stay like that and read below.

If it has a conversion burner in it, it doesn't have to stay that way. For protection of your family, their health (CO) and your property (fire risk) have the pipe elevated.

Okay, it must stay that way. Have them do the flueway over in concrete transit pipe. It must be cemented together and make sure it has a cleanout/access half way through it. I've done a few of these for various reasons and it can be safe and works very well.

Finally, if it's a really old unit truly consider getting rid of it.

Good luck and Happy Holidays.


  • Gary_14
    Gary_14 Member Posts: 4
    Flue piping in a dirt basement

    I have an oil furnace in the dirt basement of a 150+ year old residence. The crawlspace was dug deeper for a furnce installation years ago. However, the flue piping lays on the unexcavated dirt and ties into the bottom of the brick chimney. The pipe was completely replaced due to rot-through in the last three to five years. Portions of it are rotted through again. Is there a better solution?
  • Gary_14
    Gary_14 Member Posts: 4

    That's the second time someone suggested concrete. The furnace is an Oneida Royale from Utica Boiler that was installed in 1998, so it's a fairly new furnace and quite efficient.
  • Firedragon_4
    Firedragon_4 Member Posts: 1,436
    I don't understand what

    the fluepipe is doing on the ground????
    That unit vents from about 3' off the ground.

    What are we missing??
  • jim sokolovic
    jim sokolovic Member Posts: 439
    I've seen the same...

    installation no-no and effect on the pipe. The boiler is located in the deepest pit area, the flue pipe is run across dirt that is piled up (or not dug out as deep) to the height of the chimney base. I had one in a church crawlspace where the flue pipe must have been over 25 foot horizontally across the dirt, packed with soot, and so brittle it fell apart when touched. Obviously the dirt provides a constant source of moisture and minerals to interact with the pipe and cause corrosion. Worse yet, the difficulty in accessing the pipe leaves it and the chimney base to block up over the years.
  • Weezbo
    Weezbo Member Posts: 6,232
    get of the duff get a shovel and do some remidial ......

    year 2000 type alteration to the Ground First. better yet lose it from that area of the home, it cant be fun to work on, and if it is natural gas or LP i wouldnt even consider leaving it under the place...youd be better off with it in a 4X5 sq ft box ,outdoors,along side the chimmney with a pipe chase for the mechanicals.one way or the other you will have to dig it ...:) leaving it as a two three year change out for a maint man to do might end up with the building burning to the ground....
  • Gary_14
    Gary_14 Member Posts: 4
    You got the idea

    This residence is a brick church built in the 1800s. The excavated area was hand-dug and a concrete floor was poured. Unfortunately, the area surrounding it is solid rock. The chimney sits on solid rock, and the flue pipe, which rests on the ground, ties directly into the very bottom of the chimney. There are only a couple inches of room above it to the bottom of the floor joists. Originally, the chimnney only went down that far because it served a woodstove on the main floor. It is truly a This Old House situation.
  • Dale
    Dale Member Posts: 1,317
    Another little issue

    The code is quite clear about the vent connector not going to the bottom of a chimney. I guess the safer thing to do is to line the chimney so the flue will stay as hot as possible and put on a listed cap. Althouth side vent oil isn't the usual best choice you may want to look into it if you have a spot to hang the outdoor portion. what you have now isn't safe.
  • Bob Harper
    Bob Harper Member Posts: 1,026
    oil flue venting

    Per NFPA 31 and 211, the chimney should be in good condition and properly sized or it should be relined.
    Oil requires a clean out below the breeching--get a shovel.
    Single walled chimney connector carries an 18" clearance to combustibles. Sounds like you don't have that. Consider 'L' vent-9" clearance or even "all fuel chimney listed to UL 103, which carries a 2 inch clearance. Either way, you need stainless near that soil. Maintain 1/4" per foot slope up to chimney, pipe must be visible 360 degrees for inspection, 3 screws per joint on single walled, seams up, 24 gauge galv. if >6" diameter or 26ga. SS. Recommend type 316Ti alloy.
  • Gary_14
    Gary_14 Member Posts: 4

    Thanks to all who responded. I do need to do something better with this installation. As far as I can get "asking around" this heating system has been in operation since at least the 70s installed just this way. I'm not sure how often the flue piping had been replaced over that time period. I replaced the furnace when I bought the house in 98. It's a terrible setup that needs reworked. One of the mixed blessings of living in and trying to modernize an old house.
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