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Gas Piping & Electrical Bonding

I am going to install some CSST for a new HW Heater. In the install manual, it states you have to ground the gas system.

I will have to verify that I have a ground running where my gas line enters the house and connects to my water supply line, which is where the electric panel grounds to.

The question I have is do you need to jump a CSST line. In my situation, I will be removing a length of pipe and installing the CSST, do I need to run a jumper to electrically connect each end? I know the CSST fittings rely on some o-rings at the fittings, but I thought there was metal contact also.

Timothy Miller
Re: Gas Piping & Electrical Bonding

Howdy, check with you local gas Company they will tell you if you need to ground the water heater or not as it varies state to state. Some areas its a big no no to ground to gas pipe....

Re: Gas Piping & Electrical Bonding

I don't think that gas piping is a DIY project.

Re: Gas Piping & Electrical Bonding

While it is a violation of the NEC to use the gas line as a grounding electrode, it is required to bond the metal gas lines to the electrical service ground if there is a possibility they might become energized. There are many different opinions about what is meant by this, as a furnace or electric water heater might cause this to occur.
On the other hand, it is an absolute requirement of the NFPA National Fuel Gas Code to bond the gas line if CSST is used. You only need to bond the metal pipe where it is closest to the electrical service with #6 solid or (preferably) stranded wire and approved clamps. Do not bond ahead of the gas meter or any non conductive isolators that may have been installed by the utility co. to prevent conduction to the underground gas line. Do not bond around the trac pipe. It is important to keep the bonding wire as short as possible to reduce impedance, and that is why it is best to find the closest gas line to the service. You only bond the gas piping at one point and never to the CSST itself, although the fitting it is connected to is okay.

The reason for the bond is that there were numerous fires caused from nearby lightning strikes which induced currents into interior metal piping (such as trac) which subsequently arced to a grounded metal surface such as a water pipe or heater. The arc was small, but the corrugated s.s. Trac pipe is so thin that a hole would burn through, allowing gas to escape and light at the same time.

Select the Design and Installation guide and then go to page 54-56 on this link:

Re: Gas Piping & Electrical Bonding

Thanks ZZZ.

I agree that you do not want to ground to a gas system. But you need to ground the gas system. That is why all items are run to the water line for the ultimate ground where it enters the house.

I was unsure the reasoning csst had different requirements, but the burn-through makes sense. Essentually, you are trying to create paths of least resistance away from the CSST, which is a weak point electrically speaking.


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