Rotted gas pipe in fireplace - any suggestions ?

[WEldred]

Hi Terry and Forum,

My gas insert in my fireplace would light the pilot, but would shut off when I attempt to start the fireplace. So, being a good DIY'er, I vacuumed out the insert and it had the same issue. The last time I encountered this, it was a pressure issue. So - on to the issue:

I went to take the insert out and as I pulled, the top of the black pipe coming out of the floor of the hearth snapped off. Actually, it was rotted (if there is such a term for pipe) and basically crumbled.

So, here are the questions:
1: My connections went black pipe in base of hearth to copper elbow (which is actually a 1" to 1/2" converter) to stainless steel? flexible gas pipe to gas insert. Is this combination of metals ok or could the copper on black pipe have led to the rotting ?

2: From the best that I can tell (and I plan on going down in the 16" high crawl space to confirm ) the black pipe comes up in the brick work at the front of the hearth to the shutoff valve, then goes through the brick work to the back middle floor of the hearth where the black pipe sticks out about 1". Is this an easy repair or will they be tearing apart the hearth to replace this pipe ? (I know this may be a tough one to answer - I wasn't sure if there's a standard building/plumbing technique used for this type of fireplace that might make this work "easier" or if this is just one of those painful projects)



Thanks for your thoughts ! As you can tell, I don't plan on doing this work and want to make sure I have enough information to discuss this with whoever does the work.

Ward

[hj]

The codes USUALLY require that the gas pipe come out of the side of the fireplace liner about 3" above the floor to eliminate the type of problem you have. The valve is usually in the wall, NOT the floor where it could be filled with sweepings. The mix of materials is not a problem because there is no water to cause an electrolysis reaction.

[WEldred]

Hi HJ,

Thanks for the info. I think you answered the question - I had an issue with my chimney flashing that resulted in seepage into my fireplace. It's possible that was the water source that created an electrolysis reaction that you point to.

Thanks again !

Ward

[Terry]

The plumbing was put in after the brick. I think.
I would guess that there is access under the floor that gives you access to the fittings.
Brass to black pipe should be fine, however your pipe has crumbled, so regardless of that fact, it will need replacement.
Perhaps water dripping on the pipe did it's toll.

[hj]

It was NOT electrolysis, it was "RUSTING" from water being around it. Black pipe "rusts" when it gets wet.