block heater tripping GFI

[Fire1]

Mine works fine at work with multiple trucks on multiple outlets.

 

[BigDaveZJ]

What gauge is your extension cord and how long is it?

Forget the gauge but's probably 25ft and rated to 15amps.

 

[JLDickmon]

1500 watt block heater divided by 108v and a couple of dirty/corroded terminals/receptacles, and I'd say your cord is under-rated... plus it's probably too long...

I made my cord out of RV cable, and it's only about three feet (just enough to get it through the front bumper)

oh yeah, and check the cord for the heater. Chances are the cord has failed right by the plug; it's VERY common..

 

[BigDaveZJ]

The cord I'm using has handled chops saws, angle grinders, small buzz box welders, so I'm doubting that's the source of the problem. And if I could make the cord shorter I would, but it's already almost stretched to its full length and it's in the outlet closest to my truck.

 

[the cable guy]

block heater

what is the amperage rating of the GFI and the braker on the circuit?
sounds like its a 15 amp circuit which probably has some other things in the same circuit that may be operating when you plug in the block heater. the total amperage draw is most likely more than 15 amps and the GFI is tripping first.
do you have a 20 amp circuit you can use ?
make sure other appliances if possible are off when you plug the truck in for the nite

 

[RSG]

This began happening on my GFI a few years back; it was duplex connector, not a breaker. I took it out of the wall and surprise! it was fried. Replaced it with a $10-$15 newbie and has never tripped in the last year.

I don't understand exactly, but a GFI senses current imbalance between hot and ground vs neutral and ground. Maybe as they "wear out" there is some current leakage in the duplex connector itself. Anyhow, it is a cheap fix and not much lost if that doesn't fix your problem.

 

[BigDaveZJ]

what is the amperage rating of the GFI and the braker on the circuit?
sounds like its a 15 amp circuit which probably has some other things in the same circuit that may be operating when you plug in the block heater. the total amperage draw is most likely more than 15 amps and the GFI is tripping first.
do you have a 20 amp circuit you can use ?
make sure other appliances if possible are off when you plug the truck in for the nite

I have 2 dedicated 20 amp circuits in the garage, both GFI outlets. Had it one of the 20 amp circuits and it was tripping the GFI, moved it over to the other GFI and had the same problem. NOTHING else plugged into either circuit.

 

[BigDaveZJ]

This began happening on my GFI a few years back; it was duplex connector, not a breaker. I took it out of the wall and surprise! it was fried. Replaced it with a $10-$15 newbie and has never tripped in the last year.

I don't understand exactly, but a GFI senses current imbalance between hot and ground vs neutral and ground. Maybe as they "wear out" there is some current leakage in the duplex connector itself. Anyhow, it is a cheap fix and not much lost if that doesn't fix your problem.

Both GFI outlets, as well as the circuit breakers, are less than 2 years old and only see periodic use, albeit heavy use with air compressors and power tools when they are used.