AFCI & block heaters

[ptonsparky]

Called a customer to see how his super cheap radio controls were working for loading his semis. :thumbsup:

He read somewhere that suggested his semis should be plugged into AFCI receptacles to prevent fires and I am guessing he means at the truck block heater, not the building wiring. My thoughts are that a GFCI would way better suited for this than an AFCI.

Thoughts?

 

[ActionDave]

I think he is confusing AFCI with GFCI...they all look alike.

Municipality here had a block heater fault and it burned up one of their plow trucks...they got religion real quick and now they want GFCI protection everywhere.

 

[GoldDigger]

An internal short in the heating element could result in a local hot spot without tripping either a GFCI or AFCI.
and if the truck body is not grounded, there would be nothing to trip a GFCI, so whatever you use should connect an EGC to the truck "ground".


Tapatalk!

 

[ActionDave]

An internal short in the heating element could result in a local hot spot without tripping either a GFCI or AFCI.
and if the truck body is not grounded, there would be nothing to trip a GFCI, so whatever you use should connect an EGC to the truck "ground".


Tapatalk!

Yes. But politics and religion are off the table for discussion in all but the most friendly of environments. In my case GFCI protection is what was asked for, and what is code required for truck heaters.

 

[GoldDigger]

GFCI will definitely protect someone who walks up to and touches an energized truck while standing on a concrete slab. So it is a good idea and code required for that reason. I just do not necessarily see it preventing fires.


Tapatalk!

 

[Lectricbota]

An internal short in the heating element could result in a local hot spot without tripping either a GFCI or AFCI.
and if the truck body is not grounded, there would be nothing to trip a GFCI, so whatever you use should connect an EGC to the truck "ground".


Tapatalk!

Those that I have seen all have the metal part of the element base grounded--which is fastened to the engine body.

 

[kwired]

An internal short in the heating element could result in a local hot spot without tripping either a GFCI or AFCI.
and if the truck body is not grounded, there would be nothing to trip a GFCI, so whatever you use should connect an EGC to the truck "ground".


Tapatalk!

I can't recall ever seeing an engine heater of any type that did not have a cord assembly that did not include an equipment grounding conductor. I will not say that I've never seen them plugged into "two wire" receptacles or had the grounding pin removed/broken off of either the heater cord or an extension cord supplying it.

That said, just what combustible materials are around the heater that are catching fire that maybe wouldn't be subject to enough heat for combustion during normal use of the vehicle? Seems to me that vehicle had a higher risk of catching fire anyway.

Yes. But politics and religion are off the table for discussion in all but the most friendly of environments. In my case GFCI protection is what was asked for, and what is code required for truck heaters.

Most of the time the outlet supplying this application is in a location that requires GFCI protection anyway, at least for a newer installation, I guess outdoor receptacles at non dwelling locations did not generally require GFCI all that long ago. If the truck is indoors it shouldn't need the engine heater unless it is a non heated building.