kramm
January 20, 2016, 3:10am
1
Just received this, haven’t read it yet.
Over the last several years fires have occurred that have been attributed to the failure of CSST when hit by lightning.
An article by Mark Goodson, P.E. and Lee Green, P.E. has been brought to our attention, and we felt that it was important to share with you.
There has been much discussion regarding the bonding and grounding of CSST. The manufacturers believe that their instructions pointed the installer to so-called direct bonding, but their instructions also warned the user to follow the NEC. The CSST Industry has maintained that direct bonding and grounding will help prevent CSST from receiving lighting damage.
CSST (Corrugated Stainless Steel Tubing) has been used for approximately two decades to pipe and deliver fuel gas in businesses and residences in lieu of conventional black pipe. Lightning vulnerability of CSST has been documented in research. Goodson and Green outline another issue that is posed by the use of CSST – its impact on the ability of overcurrent devices to promptly clear electrical faults that are present within a structure.
http://goodsonengineering.com/wp-content/uploads/A-Hidden-CSST-Electrical-Danger.pdf
http://www.texasinspector.com/files/CSST-DANGERS.pdf
Jim_Port
January 20, 2016, 1:18pm
2
It is a shame that the issue of bonding was never discussed and whether it was in place or missing . I also did not see what the arcing was to something external or whether it was just along the tubing itself.
mlarson
January 20, 2016, 2:45pm
3
I have a piece of CSST with a hole in it from a family property.
The CSST was not bonded.
1/16" hole with obvious melting around the hole.
It was in an enclosed ceiling running through wood floor trusses and not near any grounded metal.
Apparent lighting strike to the home as we found burnt NM in a wall 20 ft. away from the CSST when we were moving a window.
Lightning is crazy stuff.
jjonas
January 20, 2016, 3:52pm
4
Not surprising, considering the composition of lightning…http://stormhighway.com/types.php
jrobinson11
January 20, 2016, 4:13pm
5
You know I completely agree. Should it be implied that the found CSST was not bonded? Has anyone ever found a CSST caused fire where they also found “proper” bonding? That is the million dollar question to me.
Also for my own knowledge, I need to look up and study information on proper bonding techniques. Do not think I saw that in the list of InterNACHI courses. I’m calling out just about every gas vent I see that goes through the attic/roof. In the few months experience I have had, I have seen only one vent where I found it was bonded. I assumed properly.
mlarson
January 20, 2016, 5:46pm
6
jrobinson11:
You know I completely agree. Should it be implied that the found CSST was not bonded? **Has anyone ever found a CSST caused fire where they also found “proper” bonding? **That is the million dollar question to me.
Also for my own knowledge, I need to look up and study information on proper bonding techniques. Do not think I saw that in the list of InterNACHI courses. I’m calling out just about every gas vent I see that goes through the attic/roof. In the few months experience I have had, I have seen only one vent where I found it was bonded. I assumed properly.
I have not but have read it has happened in studies of the issue.
Jim_Port
January 20, 2016, 11:57pm
7
Sounds like you are saying even when bonded there is an issue with the CSST. If so it sounds like bonding has no bearing on the failure rate.
mlarson
January 21, 2016, 12:57am
8
Have you read the studies?
There is so much CSST out there you should not be expecting a recall.
