Shocking Ductwork

[Phillip]

Just a reminder to all of you out there to be careful.

yesterday while inspecting the crawlspace I started sliding under the main duct line.

I felted a small tingle on my back, move and got the same feeling. I got out from under the duct work and touch it with my hand. I received a small shock.

I got looking around and found a frailed electrical wire on top of the duct work.

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[Marc]

Sure glad you're alright. Hot wire and earth contact can easily be a lethal combination, even if its just 120V.

Marc

[Terence McCann]

You get the most interesting homes Phillip - I want to inspect there. On second thought - not so much, I'll leave it to you. [:-crazy]

[Ben H]

That is a tad scary, glad you made it out OK.

[Mark P]

Seems like I remember hearing of an inspector that was killed in an attic from an electrical shock. This was 5+ years ago and I don't remember the details.

[John Kogel]

I wear a rubber rain jacket when there's wet ground like that. I know, Phil, you'd die of heat stroke in a rubber raincoat.

Well, if I die and go to Home Inspector Hell, I suspect it will be a crawlspace somewhere in your neighborhood. I'll be the sweaty guy in the rubber coat. []

[Phillip]

I wear a rubber rain jacket when there's wet ground like that. I know, Phil, you'd die of heat stroke in a rubber raincoat.

Well, if I die and go to Home Inspector Hell, I suspect it will be a crawlspace somewhere in your neighborhood. I'll be the sweaty guy in the rubber coat. []

ROFLMAO[:-bigmout

[Bill Kibbel]

I was in a damp crawlspace and "discovered" the foil vapor barrier stapled up under the joists was energized. Woke my ass up.

[Phillip]

I was in a damp crawlspace and "discovered" the foil vapor barrier stapled up under the joists was energized. Woke my ass up.

An it did it in a hurry

[Marc]

I guess if the electricity is going to leak or spread, the duct work would be the place where it goes. Although wouldn't the frayed wire cause the circuit to flip? I know when I was little in our basement, we had concrete floors and exposed light switches where my father was renovating. Touching one of those wires would really wake me up.

If the duct work was solidly bonded to earth, the breaker would likely trip. If bonding were not present, the energized duct would just sit and wait for some unfortunate individual or animal to complete the path, though that probably wouldn't be enough conductivity to trip the breaker.

Marc

[Jim Katen]

. . . If the duct work was solidly bonded to earth, the breaker would likely trip.

Possible, but not guaranteed. It would depend on the earth.

If bonding were not present, the energized duct would just sit and wait for some unfortunate individual or animal to complete the path, though that probably wouldn't be enough conductivity to trip the breaker.

Marc

If the goal is to clear faults that occur on the ducts, the way to achieve that is to use a bonding jumper to connect the ducts to the electrical system's grounding system -- either to the service enclosure, the neutral conductor at the service, grounding electrode conductor at the service, or directly to one of the service grounding electrodes. Simply connecting them to the earth won't provide a reliable fault current path.