Bonding of corrugated stainless steal tubing for gas heater in garage.

Ohms law

Senior Member
Location
Sioux Falls,SD
I had a heating and cooling company ask me to bond there CSST tubing to the ufer ground. I said sure but the ufer ground was somewhat buried in a outside wall en-cased in spray foamin a finished room.
The homeowner cut away some sheet rock in the garage so I could see the side of the panel. I wanted to bond inside the panel, the local mechanical inspector told me that it had to go directly to the ufer ground, since the underground water line was PVC. I did not understand why I could not go into the panel.

In the mechanical code book it states must have a continuous run and bond to a effective ground fault path.

Any thoughts or suggestion would be great.
 

Ohms law

Senior Member
Location
Sioux Falls,SD
I remember the mechanical inspector referring to lightning issues and how it can cause little pin holes in the CSST tubing if it became energized from lightning. I'm still confused why I couldn't go to the panel. 250.5 says "The earth shall not be considered as an effective ground-fault current path."
 

GoldDigger

Moderator
Staff member
I remember the mechanical inspector referring to lightning issues and how it can cause little pin holes in the CSST tubing if it became energized from lightning. I'm still confused why I couldn't go to the panel. 250.5 says "The earth shall not be considered as an effective ground-fault current path."
SWAG: One reason is that for lightning induced surges (not direct hits), you really need to bond the two ends of the pipe so that current does not flow AND keep it as close to ground as possible so that there are no spark discharges from the pipe to grounded metal.

IMHO the Mechanical Code reference to an effective fault clearing path is just a hangover of the general misconception that the ground and fault clearing path mean the same thing. They took the wording from the NEC without realizing that what they needed to have was something entirely different. :(
 
Last edited:

jxofaltrds

Senior Member
Location
Mike P. Columbus Ohio
Occupation
ESI
I remember the mechanical inspector referring to lightning issues and how it can cause little pin holes in the CSST tubing if it became energized from lightning. I'm still confused why I couldn't go to the panel. 250.5 says "The earth shall not be considered as an effective ground-fault current path."
It is not there to clear a fault. Lightning is not a fault.

Here is one manufacturer: http://www.wardflex.com/bonding_faq.htm
 

Ohms law

Senior Member
Location
Sioux Falls,SD
SWAG: One reason is that for lightning induced surges (not direct hits), you really need to bond the two ends of the pipe so that current does not flow AND keep it as close to ground as possible so that there are no spark discharges from the pipe to grounded metal.

IMHO the Mechanical Code reference to an effective fault clearing path is just a hangover of the general misconception that the ground and fault clearing path mean the same thing. They took the wording from the NEC without realizing that what they needed to have was something entirely different. :(
That makes perfect sense. I read a similar article on how this is a common mis conception and that nobody really cares.

One more question what is Art. 250.104(B) in relation to?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
...
One more question what is Art. 250.104(B) in relation to?
It is the NEC rule that actually covers the bonding of gas piping. The rule that covers the extra bonding of the CSST is in NFPA 54,(Fuel Gas Code) and in the manufacturer's instructions.
The proposal to put the CSST bonding rule into the NEC was rejected by CMP 5 because there is was technical substantiation that supports the idea that the extra bonding required by the manufacturer's and NFPA 54 will solve the problem with CSST, near by lighting strikes and homes burning.
 

jxofaltrds

Senior Member
Location
Mike P. Columbus Ohio
Occupation
ESI
Can you be more specific, please? Is this referring to you local energy company's incoming gas line? I feel like I should know this, sorry if this is a stupid question.
NO not the utility lines coming in. If metal that would make it an electrode. NOT allowed.

You could have sprinklers, gas lines (as Don said), air lines etc using metal. Thought I had a graphic but cannot find it at this moment.
 

Gregg Harris

Senior Member
Location
Virginia
Thank you.
2012
SECTION 310 (IFGS) ELECTRICAL BONDING

310.1 Pipe and tubing other than CSST.

Each above-ground portion of a gas piping system other than corrugated stainless steel tubing (CSST) that is likely to become energized shall be electrically continuous and bonded to an effective ground-fault current path. Gas piping other than CSST shall be considered to be bonded where it is connected to appliances that are connected to the equipment grounding conductor of the circuit supplying that appliance. 310.1.1 CSST.
Corrugated stainless steel tubing (CSST) gas piping systems shall be bonded to the electrical service grounding electrode system. The bonding jumper shall connect to a metallic pipe or fitting between the point of delivery and the first downstream CSST fitting. The bonding jumper shall be not smaller than 6 AWG copper wire or equivalent. Gas piping systems that contain one or more segments of CSST shall be bonded in accordance with this section.
Same verbiage for
International Residential Code G24.11.1.1
NFPA 54 7.13.2

This is what NJ position on who does the bonding
"Motion was made and seconded, and unanimously passed, that although a New Jersey licensed electrical contractor is the most qualified person to perform the bonding, the Board's position that it is not required that a licensed electrical contractor install the bonding clamps and conductor provided that the connection to the grounding electrode system is outside the service enclosure; i.e. to the electrical system grounding electrodes with the appropriate ground clamp, to the foundation rebar when the electrical system employs a Ufer-ground, to the electrical system grounding electrode conductor if it is of sufficient size, to other grounding electrodes (lightning) if integrated with the electrical system, or copper water pipe if it serves as primary grounding electrode. The Board notes that this position is applicable only for installations required to be inspected and are inspected per the State Uniform Construction Code."

NFPA 54 will have changes based on the final report studies from GTI limiting the length and adding a bonding jumper to manifolds
 

Ohms law

Senior Member
Location
Sioux Falls,SD
2012
SECTION 310 (IFGS) ELECTRICAL BONDING

310.1 Pipe and tubing other than CSST.

Each above-ground portion of a gas piping system other than corrugated stainless steel tubing (CSST) that is likely to become energized shall be electrically continuous and bonded to an effective ground-fault current path. Gas piping other than CSST shall be considered to be bonded where it is connected to appliances that are connected to the equipment grounding conductor of the circuit supplying that appliance. 310.1.1 CSST.
Corrugated stainless steel tubing (CSST) gas piping systems shall be bonded to the electrical service grounding electrode system. The bonding jumper shall connect to a metallic pipe or fitting between the point of delivery and the first downstream CSST fitting. The bonding jumper shall be not smaller than 6 AWG copper wire or equivalent. Gas piping systems that contain one or more segments of CSST shall be bonded in accordance with this section.
Same verbiage for
International Residential Code G24.11.1.1
NFPA 54 7.13.2

This is what NJ position on who does the bonding
"Motion was made and seconded, and unanimously passed, that although a New Jersey licensed electrical contractor is the most qualified person to perform the bonding, the Board's position that it is not required that a licensed electrical contractor install the bonding clamps and conductor provided that the connection to the grounding electrode system is outside the service enclosure; i.e. to the electrical system grounding electrodes with the appropriate ground clamp, to the foundation rebar when the electrical system employs a Ufer-ground, to the electrical system grounding electrode conductor if it is of sufficient size, to other grounding electrodes (lightning) if integrated with the electrical system, or copper water pipe if it serves as primary grounding electrode. The Board notes that this position is applicable only for installations required to be inspected and are inspected per the State Uniform Construction Code."

NFPA 54 will have changes based on the final report studies from GTI limiting the length and adding a bonding jumper to manifolds
This was great!

I love this forum. Everyone is just awesome and so informative.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
The NFPA 54 rule is the rule, but there is just no technical evidence that the bonding solves the problem. CMP5 asked the proposers for technical evidence to support the idea that the bonding will prevent the lightning damage that was causing fires, and the submitters could not provide any such evidence that would convince CMP 5 to put the rule into Article 250.

Based on this lack of evidence, if I was building a house in an area that has thunderstorms, I would not even consider CSST for my gas piping.

That being said, there are codes and instructions that require the CSST to be bonded and the EC might as well do it, as long as he gets paid to do it.
 

GoldDigger

Moderator
Staff member
This is what NJ position on who does the bonding
"Motion was made and seconded, and unanimously passed, that although a New Jersey licensed electrical contractor is the most qualified person to perform the bonding, the Board's position that it is not required that a licensed electrical contractor install the bonding clamps and conductor provided that the connection to the grounding electrode system is outside the service enclosure; i.e. to the electrical system grounding electrodes with the appropriate ground clamp, to the foundation rebar when the electrical system employs a Ufer-ground, to the electrical system grounding electrode conductor if it is of sufficient size, to other grounding electrodes (lightning) if integrated with the electrical system, or copper water pipe if it serves as primary grounding electrode. The Board notes that this position is applicable only for installations required to be inspected and are inspected per the State Uniform Construction Code."
So, based on extrapolation beyond all reasonable certainty, I would say that the inspector is taking a requirement that non-electricians connect outside the service enclosure and is applying it to electricians too because he is not as well read as electrical inspectors. :angel:
 

Gregg Harris

Senior Member
Location
Virginia
So, based on extrapolation beyond all reasonable certainty, I would say that the inspector is taking a requirement that non-electricians connect outside the service enclosure and is applying it to electricians too because he is not as well read as electrical inspectors. :angel:
It keeps getting tossed around.
Technically bonding should be performed by the electrician. Electricians do not want to bond it because, . well I have not a clue. So different municipalities are tossing the idea that if the plumber or mechanical contractor does not need to go into the panel (which they do not)
that it would be ok for them to do.
 
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