Thread: Fireplace gas stub

Are you allowed to burn wood in a fireplace if it has a gas line stubbed out from the side. There is a key type shutoff for the gas on the face of the fireplace just below the mantel, so I am thinking yes, but the valve could be open and you would not know it because there is a cap on the stub. Which leaves gas in the pipe, next to a roaring fire, so I don't know.

Similar Threads:

• Outdoor fireplace
• Prefab Fireplace Clearances
• Gas Fireplace Chimney Clearance
• Wood Burning Fireplace
• Fireplace Had It's Own Air Handler Unit

Mathew,
I would say yes. there are a lot of fireplaces here that have a gas starter, a gas pipe across (under) the grate to start a fire in the fireplace, then turn the gas valve off, easy to start a fire.
I always recommend installing a gas log kit. No mess, ashes, hauling the wood into the house. JUST BE SURE TO LEAVE THE DAMPER OPEN TO ALLOW THE UNSPENT GASES TO EXIT THE HOUSE THROUGH THE CHIMNEY.

what's it going to do? Start a fire in the fireplace?
It takes a fuel/air mixture to burn. There is only the fuel component in the pipe and no air so now danger of fire. I've seen the gas company guys heat an old metal gas line to red hot with a rosebud and fold it over to cap it off when abandoning it to be replaced with a new plastic line.
Gas is not as dangerous as some think. Has to have just the right conditions to burn.
I've worked the system live many times to avoid needing to relight all the pilots. It's only about a half pound pressure, you can stop it off with your finger.
Dana

Matthew....

Is this a new house? That looks like a prefab gas fireplace with no vent.

This is just a question.

No difference than having gas in there to a gas log lighter.

Originally Posted by Matthew Barnicle

Are you allowed to burn wood in a fireplace if it has a gas line stubbed out from the side. There is a key type shutoff for the gas on the face of the fireplace just below the mantel, so I am thinking yes, but the valve could be open and you would not know it because there is a cap on the stub. Which leaves gas in the pipe, next to a roaring fire, so I don't know.

I think that MB's question comes from not knowing if the gas valve is off or not. When you have a burner in the fireplace, the gas is shut off some distance away from the firebox. With a capped valve, you may not know if the valve is off and whether or not the cap might be leaking. I can't see it as a huge issue. Bob Harper has indicated that he does not like the keyed valves because they can leak. Assuming he is referring to leaking out around the valve rather than leaking into the pipe that is connected to the appliance, the chances of a leak at the cap are likely less than leaking at the valve. Too much to worry about.

There are codes, there are perceived hazards and there are real hazards we must consider with any situation when deciding what to report or call out. This is a case where there is no clear cut answer in any of the codes. You are allowed gas pipes into woodburning fireplaces either for log lighters or gas logs, whether vented or ventfree. If the fireplace is factory built, it must allow such gas pipes, it must have a conduit provided for such piping, and it must state in the listed instructions what appliances are approved for use in their fireplace such as log lighters, vented logs and ventfree logs.

As Gunnar noted, I have found a significant incidence rate of fugitive gas leaks with the old style key valves, which take 21 throws of the wrist. I have not noticed hardly any leaks from the newer 1/4 turn non-displaceable fully ported ball valve type. This includes leaks downstream within the piping and into the room. I guess things are getting better for a change.

The codes do not address the issue of stubbing out a gas line into a masonry fireplace or capping off the line to an appliance. I, too was concerned about this issue so I called Ted Lemoff, who wrote NFPA 54 and is their staff technical advisor. He assured me if there was a single incident involving gas captured btw the shutoff and cap in the firebox leading to a single fire or explosion, it would be addressed in the codes. The only thing they caution is not to allow gas piping to be exposed to full flame impingement. For instance, log lighters miraculously have an excellent safety record in spite of their potential for problems. Deliberately building a wood fire on top of the log lighter nightly seems crazy to me but they just don't blow up.

The larger hazard here is if the pipe penetration is not properly sealed to the refractory panel and the inner firebox wall at the conduit.

That facing and mantel seem awfully skinnny at the sides of the firebox. Aside from looking disproportionate, you need to check the listed instructions. Most factory builts do not state a flat requirement for non-combustible surrounding the sides but rather use a formula such as anything combustible must be in the shaded zone of an illustration. This uses a triangle formed from the rear corner of the firebox to the opposing outer edge of the firebox. For flush facings, it may work out to about a 38 degree angle and about 54 degrees for a 4 inch brick facing, as one example. Again, this varies by mfr. and even model.

I can't tell if the marble hearth extension is above the floor or not. When you see flush HX, suspect no required insulation board under the HX. Again, consult the listed instructions.

HTh,
Bob

Bob,

To continue one of my thoughts:

You have indicated that the keyed valves are more prone to leaking than a ball valve. My concern with a non-keyed valve is when some toddler comes along and turns that 1/4 turn and the gas flows uninterrupted into the fireplace. The advantage of the keyed valve is that the key can be removed and put up high where little Johnny can't get to it. I suppose the handle can be removed from the ball valve, but that is not intuitive.

With a log lighter, that is one of my main concerns. I simply do not understand why more people have not been injured over the years by these things. However, ideally, log lighters have two valves:
one to throttle the flame and a shutoff upstream. Hold your breath on that one...

The OP, however, discussed a capped gas line so even if the shutoff was left open, it won't go anywhere. I know of no incidents involving a capped gas stub-in relative to a gas fire or explosion. There are cases of fire extension through the unsealed conduit into the chase. There is the possibiliy of ignition inside the chase from heat conduction down the iron pipe as several mfr.s have stated clearances for this pipe as it exits the fireplace outer wrap. It would take a Level III or fire to access this area but it is a concern.
Bob