Run gas line to firebox through cleanout or through brick?

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dave11

Minister of Fire
Hearth Supporter
May 25, 2008
633
Western PA
This is actually masonry question. I want to run a NG line into an unused firebox that had burned only wood. I've done a lot of black pipe work, have all the tools etc. Question is the best way to run it. There is a small ash dump at the back of the firebox, it goes down to an ash pit in the basement, though they are not in line with each other, the cleanout door is offset about one foot from the firebox ash door.

A black pipe gas line was installed originally as a fire starter, it is still there but has been cut off in the basement. It runs along the basement ceiling, up across the top of the pedestal that sits in front of the hearth (beneath a marble slab), then below the firebrick on the floor of the firebox, then turns and comes up into the firebox. The end there was crushed at some point and is unusable.

So there are two options. 1) Drill through the wall of the ash dump in the basement and run CSST up into the firebox. This seems to be the standard way, but the problem is that it looks like there are at least two, and maybe three brick courses in that part of the chimney. I have a two inch diamond core bit I was going to use, but it won't get through more than one course of brick, and I certainly can't drill from the other side. To run through the cleanout door itself wouldn't be good since it is only two feet off the floor.

2) Break out the necessary bricks on the floor of the firebox, and run black pipe in similar to the way it was done originally, then replace the bricks. I believe I'd need to metal-sleeve the pipe, but there certainly wasn't a sleeve originally. I'm less enthusiastic about this because I haven't done much brick work, but maybe this is a chance to learn.

Appreciate any advice.
 
If the floor of the firebox is a standard fire brick I'd take a shot at removing the bricks. If you have to destroy a brick, no big loss, just install a new one. You may still have to drill though to get through the mortar bed. At least getting the top brick out of the way should make drilling through what's below easier.

The trouble with drilling through multiple courses of brick is that many times rubble is used as filler and can be tough to drill through without binding up or breaking your bit.
 
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Thanks semipro. The brick on the firebox floor does look like typical thicker firebrick. I'd need to break out two of them to re-run the black pipe along the floor.

I've been having trouble though finding the relevant code for this though. Nowadays black pipe would need to be sleeved before running through a mortar bed beneath bricks, correct? But since it's a firebox, the sleeve would need to be metal, not pvc, is that right?
 
Thanks semipro. The brick on the firebox floor does look like typical thicker firebrick. I'd need to break out two of them to re-run the black pipe along the floor.

I've been having trouble though finding the relevant code for this though. Nowadays black pipe would need to be sleeved before running through a mortar bed beneath bricks, correct? But since it's a firebox, the sleeve would need to be metal, not pvc, is that right?

My understanding on pipe liners is that they recommended or required to prevent the high pH of the mortar from corroding the pipe that might result in a leak.

Perhaps you could run stainless steel gas line through the masonry portion?
 
The CSST I've worked with still requires a sleeve for any burial in concrete; I assume the same goes for mortar. Also, it needs to be a plastic sleeve, not metal, which seems like the wrong thing to do in a firebox. Plus you can't make a tight 90 degree turn with CSST.

The original black pipe line has been there 67 years and looks fine, I think I'll just duplicate what was done originally, but add a metal sleeve.
 
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