GFCI outlet tripping on house

[DuneElliot]

Bear with me while I explain this.

I have not moved my fifth wheel in a while and have a 100ft 14AWG extension cord running from the shore power cord to a GFCI outlet on my house to run an oil-filled free standing heater in the camper. I have had it set up this way for over two months and have not had an issue. As of last Sunday this set-up is tripping my GFCI outlet anywhere between 2 hours and 14 hours after being plugged in. It never trips immediately.

I have not added or detracted from my electrical components on the 110V circuit except for a new breaker (a month ago), and my inverter is not yet wired in. The only recent things I have done have nothing to do with electrics and I have added nothing onto the walls. I have nothing else running and all other breakers are in the Off position. I have been able to run the heater on high, lights and TV/PS3 console all at the same time up until this point.

My camper GFCI outlets and the regular outlets are on two separate circuits and breakers and plugging the heater into either one causes the same tripping of the house GFCI. Nothing trips in the camper.

I have tried a different extension cord, different 30-15A plug converter, different heater, different outlets (GFCI and regular circuits), different GFCI outlet on the house and still it trips. The 30A plug and converter plug are protected from the weather in one of the wheel wells. I have plugged the heater directly into the extension cord from the house through a window and it does not cause the GFCI outlet to trip.

I realize that this means there is an electrical issue somewhere but this has me completely stumped. I did have a few leaks in the bathroom (which are now fixed and were mostly dried up immediately. Is it possible some of the excess water, plus all the moisture we've been having got into the circuit somewhere? The shore power cord is in the panel between the living area and the bathroom so did get some water in it because of the bathroom leaks.

 

[caretaker]

i wonder if the outlet its self is going bad?,,,or maybe try un plugging each device until it doesn't happen anymore,,(example: you unplug the heater, it stops doing it would probably be the heater) to make sure it isn't one of them,,,its probably going to be a process of elimination, so start with the easy stuff first.

 

[Optimistic Paranoid]

You say the GFCI outlet that is tripping is in yout house and not an outlet in your 5th wheel, right?

Are there other outlets on the same circuit as your GFCI?  It is quite common to wire several regular outlets "downstream" of the GFCI outlet, and that way it protects all of them, too.  You could have a problem with a downstream outlet that is causing the GFCI to trip.

In fact, I heard of one case where a spider had built a nest in an unused downstream outlet, and when it rained, the web attracted moisture and that's what was causing the problem.

 

[GotSmart]

I had one where there was a lose wire connection (in the system)  that would heat up after several hours.  Another where the GFCI was old and replaceing it solved the priblem.  Another where there was aluminum wires that periodicaly needed tightning. 

Take these as possibilities.

 

[DuneElliot]

i wonder if the outlet its self is going bad?,,,or maybe try un plugging each device until it doesn't happen anymore,,(example: you unplug the heater, it stops doing it would probably be the heater) to make sure it isn't one  of them,,,its probably going to be a process of elimination, so start with the easy stuff first.

As mentioned in the OP I have literally switched everything out. Different cord, different outlet (both in and outside the camper), different plug, different heater. 

You say the GFCI outlet that is tripping is in yout house and not an outlet in your 5th wheel, right?

Are there other outlets on the same circuit as your GFCI?  It is quite common to wire several regular outlets "downstream" of the GFCI outlet, and that way it protects all of them, too.  You could have a problem with a downstream outlet that is causing the GFCI to trip.

In fact, I heard of one case where a spider had built a nest in an unused downstream outlet, and when it rained, the web attracted moisture and that's what was causing the problem.

Yes, the outlet on the house NOT the camper. It doesn't trip unless the camper is plugged in, and I think when the heater is running. (I haven't checked it to see if it trips without the heater on and just having the camper plugged in with nothing running).

I have nothing plugged in to other outlets and it doesn't trip when the heater is plugged directly to the outlet via extension cord.

I had one where there was a lose wire connection (in the system)  that would heat up after several hours.  Another where the GFCI was old and replaceing it solved the priblem.  Another where there was aluminum wires that periodicaly needed tightning. 

Take these as possibilities.

GFCI is fine at all other times. I will check for loose wires this weekend.

This started happening right after I flooded the bathroom a couple of time and water went under the wall into the storage compartment for the shore power cord (the plug was still outside though).

 

[GotSmart]

This started happening right after I flooded the bathroom a couple of time and water went under the wall into the storage compartment for the shore power cord (the plug was still outside though).

Possibility.  Open things up, and set up a fan.  Use a hair dryer to complete disiccate that area.

 

[rvpopeye]

It sounds like you have done some good troubleshooting already.

Unplug from the house and tighten all the wires to the breakers , neutral and ground buss bars in the camper breaker box.
Maybe check all the outlets too.
If the 30 amp plug isn't molded on check the screws in there .
Do the plug prongs look shiny or dull , black and maybe plastic melted?
Also open up that wet compartment and dry it out , use one of the heaters on low if the weather isn't cooperating (keep an eye on it so it doesn't get too hot in there)

Intermittent wiring problems can be a pain to cure.......hope you find it.

 

[highdesertranger]

GFI's do go bad after time. get yourself a tester with a GFI tripper and start checking all your outlets and the GFI you are plugged into. https://www.amazon.com/s/?ie=UTF8&k...qmt=e&hvbmt=be&hvdev=c&ref=pd_sl_95ckanyvrt_e . highdesertranger

 

[DuneElliot]

It sounds like you have done some good troubleshooting already.

Unplug from the house and tighten all the wires to the breakers , neutral and ground buss bars in the camper breaker box.
Maybe check all the outlets too.
If the 30 amp plug isn't molded on check the screws in there .
Do the plug prongs look shiny or dull , black and maybe plastic melted?
Also open up that wet compartment and dry it out , use one of the heaters on low if the weather isn't cooperating (keep an eye on it so it doesn't get too hot in there)

Intermittent wiring problems can be a pain to cure.......hope you find it.

Definitely a couple of things I hadn't thought about there...prongs of the 30A plug. It is molded so can't get into it. They are dull. I will check all connections.
I was planning on opening up the compartment. I thought I had everything dried out with fan and heater but I didn't open it up.

GFI's do go bad after time.  get yourself a tester with a GFI tripper and start checking all your outlets and the GFI you are plugged into.  https://www.amazon.com/s/?ie=UTF8&k...qmt=e&hvbmt=be&hvdev=c&ref=pd_sl_95ckanyvrt_e .  highdesertranger

It's tripping every outlet I try, on different circuits. It's not tripping with the heater plugged straight into the GFCI outlet, just when the heater is plugged into the camper which is then plugged into the outlet.

 

[speedhighway46]

100' of 14 gauge to run a heater. I'd suspect the extension cord. Probably a made in China cheapie one. If you have a megger you could check the cord; I suspect insulation is breaking down; heat build up is tripping the GFI.

Try another cord; 12 gauge would work MUCH better.

Just my opinion . . .

 

[DuneElliot]

100' of 14 gauge to run a heater. I'd suspect the extension cord. Probably a made in China cheapie one. If you have a megger you could check the cord; I suspect insulation is breaking down; heat build up is tripping the GFI.

Try another cord; 12 gauge would work MUCH better.

Just my opinion . . .

As mentioned in the OP, I can run the heater on the cord if I plug it in to the extension cord directly. It is ONLY when I plug the heater into the camper outlets and then the camper into the extension cord that it trips the GFCI. I have also tried 2 separate extension cords and I end up with the same result.

 

[highdesertranger]

the testers I linked to test all outlets for faults including GFI's. highdesertranger

 

[Dennis]

With all the other trouble shooting you have done and you have no problems running the heater when by passing the shore power cord/outlet it seems it would be one of those items.

 

[Every Road Leads Home]

I was having a similar issue over the winter, I was plugging the camper into a garage outlet that was a GFI. It kept tripping at different times, sometimes right after I started the heater, sometimes hours later. Changed all sorts of stuff around, still tripped it. So I plugged one one of those regualr office type surge protectors into the garage GFI outlet, then the extension cord into that. Never tripped again.

 

[DuneElliot]

With all the other trouble shooting you have done and you have no problems running the heater when by passing the shore power cord/outlet it seems it would be one of those items.

Yeah, just gotta figure out which one. I change the whole system at the same time so nothing was the same. I'm going to try checking the connections today as soon as I can get outside to shovel the snow!!! 

I was having a similar issue over the winter, I was plugging the camper into a garage outlet that was a GFI.  It kept tripping at different times, sometimes right after I started the heater, sometimes hours later.  Changed all sorts of stuff around, still tripped it.  So I plugged one one of those regualr office type surge protectors into the garage GFI outlet, then the extension cord into that.  Never tripped again.

Okay. I will try that too. Thanks.

 

[gargoyle]

My garage GFCI's do not like 100 ft. extension cords. The draw of the added length is enough to trip them.
I've also experienced this in the construction work I did. Any sudden surge on the outlet, via the extension cord (starting up the table saw per se) would blow the GFCI. The sudden surge/pull of your heater starting up would do the same.
Replacing the GFCI outlet with a newer model (less sensitive) would sometimes remedy the situation.
Or replace the GFCI with a standard outlet.

 

[DuneElliot]

Found a slightly loose ground connection in the shore cord to trailer wiring junction box. Tightened that up. No evidence of moisture but a lot of twigs! Going to check other connections too, although hard to get to.

 

[Optimistic Paranoid]

You might use that DeOxit stuff that Sternwake is always raving about to clean up all the connections as you go.

 

[DuneElliot]

All connections clean and solid. I have been running the heater off the same extension cord and had the camper plugged into another, shorter, extension cord with a couple of things running. Nothing has tripped.

 

[DuneElliot]

Something very telling just happened. Still have everything hooked up and running as in this ^^^ post. Has been that way since 2pm yesterday afternoon and running well.

Was in the 5W putting up a couple of hooks. Turned the heater from Min to Max...5 minutes later the GFCI tripped. Plug at the house socket was warm to the touch.