ECN Forum
Posted By: ga.sparky56 bonding gas line - 12/16/02 01:59 AM
In my area, all gas piping is done by the propane company. They are using "trac-pipe" which looks like metallic liquidtite only with a yellow coating. Runs all the way to furnace or WH. Except for avery short pipe nipple in some cases there is noplace to put a clamp. any suggestions? No AHj or inspections here. Thanks in advance.
Posted By: Electricmanscott Re: bonding gas line - 12/16/02 03:08 AM
Bonding gas lines is accomplished through the equipment that is likely to energize the line. Example: the furnace that this line goes to has an equipment ground that serves the furnace. This also bonds the piping because it is connected to the furnace as well.
Posted By: ga.sparky56 Re: bonding gas line - 12/16/02 05:02 AM
Thanks Scott, what we usually run into here is the heating/ac guys will put acord and plug on the furnace, and we are expected to put a recep next to the furnace,unplug cord no more bond. Iguess we should insist on a disconnect/hardwire setup. This area is very similar to what sparky66wv deals with. We get alot of heat for trying to comply with nec.
Posted By: Electricmanscott Re: bonding gas line - 12/16/02 11:44 AM
If you unplug the equipment that is likely to energize the piping you lose your bond. You also don't have equipment likely to energize the piping. So is there a seperate bond required in this case? I am not sure.
Posted By: Redsy Re: bonding gas line - 12/16/02 12:22 PM
ga.spark,

A cord & plug for a furnace would appear to violate 400.7 (8).
Is this practice common with anyone else?
Posted By: ga.sparky56 Re: bonding gas line - 12/17/02 01:39 AM
Redsy Ithink you are right,afurnace is probably not listed for use with acord and plug.I will not be guilty of this again. But what if I have say one or two fireplaces with gas logs with no electrical hookup? Do I need to find amethod to bond this?
Posted By: classicsat Re: bonding gas line - 12/17/02 03:16 PM
My brother's gas water heater has a factory
cord/plug. In fact, all the assisted vent gas WHs I've seen has factory cord/plugs on them.
Posted By: ayrton Re: bonding gas line - 12/17/02 03:26 PM
Why would you "bond" gas pipe? In Art 250-52B (1) Metal undrgrnd gas pipe as no no.
Understand you are not talking about underground, but don't you think making gas line a ground could be a hazard?
As a rule I never use a gas line of any kind to bond!
Posted By: caselec Re: bonding gas line - 12/17/02 04:31 PM
ayrton - Read 250.104(B) for your answer.
Posted By: resqcapt19 Re: bonding gas line - 12/17/02 07:37 PM
ayrton,
You appear to be confusing the bonding (250-104) of the gas pipe with using it as a grounding electrode (250.52(B)(1). You can't use the undergroud gas piping as a grounding electrode because that could create a hazard for the gas company if there was a current flow and they took the pipe apart. It would also interfer with their cathodic protection of the underground metal gas piping. The gas companies install dielectric fittings between the undeground and interior piping systems. The interior gas piping must be bonded to prevent a shock hazard. If a gas appliance with an electrical connection would have a ground fault, or if an improperly installed cable would fault to the gas pipe, the bonding would prevent a shock hazard. Note that this bonding is also required by the Fuel Gas Code, not just the electrcial code.
Don
Posted By: ga.sparky56 Re: bonding gas line - 12/18/02 04:06 AM
The type of piping I was originally refering to has a rubber or vinyl coating on it.The only place it has exposed metal is at the termination points.Would this exempt it from bonding?Ilooked at the gas line at the house I am working on now, soft copper tubing from the tank to the house, goes into a regulator,then changes to trac-pipe then into house,no dielectric fitting that I could see. I looked at 2 more houses close by,same setup.
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