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Hello. Found this forum and am hoping for some assistance with a new GFCI breaker circuit for a bathroom wall heater. I think I need access to the DIY section of the forum, first though? The link provided to contact a staff member for access does not seem to take me to the right place. Thank you.
 
While I await authorization for entry into the DIY forum, I guess I can post my request for advice here. I added a circuit off my service panel for a wall heater in my bathroom. See attached diagram for specifics. I thought it best to use a GFCI breaker since the heater is in the bathroom, and that is what is giving me trouble. The GFCI trips whenever I connect the heater to it. I've tried numerous iterations of devices to troubleshoot and GFCI+heater seems to be the issue.

GFCI breaker neutral pigtail is attached to service panel neutral/ground bar.

Single run of 12/2 from service panel to switch junction box. 12/2 ground attached to service panel neutral/ground bar. 12/2 neutral and line attached to GFCI breaker. About 75ft run.

I want to have a timer switch, but to pull that variable out of the system, I'm just using a standard on/off switch right now. I understand using a timer switch that requires a neutral connection often trips the GFCI, and I'm not finding any 1500W+ timer switches that do not require a neutral. Anyhow...

The standard switch has line and load connected, as well as a ground jumper from where the 12/2 grounds are married in the junction box.

From the switch I have a short 3ft+/- run of 12/2 to the heater. The heater has pigtails for load and neutral, and a ground screw. Nothing fancy. The heater has a fan and coils.

What gets me is that even if the switch is OFF, the GFCI still trips. If there is no circuit completion, there should be no difference in outgoing & incoming current to measure, right?

I disconnected the heater and attached an outlet instead. Works just fine, including when a load is applied to the outlet.

So it seems to me that the switch and both runs of 12/2 wiring is OK, but there is something "wrong" with the heater?

I connected the heater to a nearby non-GFCI circuit using the same switch & 3ft of 12/2 and it works just fine.

Thank you for whatever help you are able to offer. I feel like I've run through all the troubleshooting I can.
 

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It sounds like the heater itself is at fault if it works fine in a non GFCI outlet, but trips your new circuit.

can you test it in another GFCI protected outlet?

It may or may not be repairable.
If bought new, can it be taken back for a replacement?

Another one for @Megawatt to advise on.
 
Not familiar with US regs but should there not be some sort of isolator near the wall heater.

also remember the live conductor may be isolated, but the ground and neutral are not so tripping may still occur if there is a fault.

agree @Megawatt will have a better understanding.
Hello. Found this forum and am hoping for some assistance with a new GFCI breaker circuit for a bathroom wall heater. I think I need access to the DIY section of the forum, first though? The link provided to contact a staff member for access does not seem to take me to the right place. Thank you.
Hineken you just told me what is wrong and you stated that the neutral wire attached to the GFCI breaker is terminated to the neutral bar but the neutral in your cable has to terminate on the breaker not the neutral bar. That’s why it’s tripping when you turn it on.
 
To me it is connected correctly if you look at his diagram. He doesn't say the neutral of the cable is at the neutral bar he says it is at the GFCI.
 
While I await authorization for entry into the DIY forum, I guess I can post my request for advice here. I added a circuit off my service panel for a wall heater in my bathroom. See attached diagram for specifics. I thought it best to use a GFCI breaker since the heater is in the bathroom, and that is what is giving me trouble. The GFCI trips whenever I connect the heater to it. I've tried numerous iterations of devices to troubleshoot and GFCI+heater seems to be the issue.

GFCI breaker neutral pigtail is attached to service panel neutral/ground bar.

Single run of 12/2 from service panel to switch junction box. 12/2 ground attached to service panel neutral/ground bar. 12/2 neutral and line attached to GFCI breaker. About 75ft run.

I want to have a timer switch, but to pull that variable out of the system, I'm just using a standard on/off switch right now. I understand using a timer switch that requires a neutral connection often trips the GFCI, and I'm not finding any 1500W+ timer switches that do not require a neutral. Anyhow...

The standard switch has line and load connected, as well as a ground jumper from where the 12/2 grounds are married in the junction box.

From the switch I have a short 3ft+/- run of 12/2 to the heater. The heater has pigtails for load and neutral, and a ground screw. Nothing fancy. The heater has a fan and coils.

What gets me is that even if the switch is OFF, the GFCI still trips. If there is no circuit completion, there should be no difference in outgoing & incoming current to measure, right?

I disconnected the heater and attached an outlet instead. Works just fine, including when a load is applied to the outlet.

So it seems to me that the switch and both runs of 12/2 wiring is OK, but there is something "wrong" with the heater?

I connected the heater to a nearby non-GFCI circuit using the same switch & 3ft of 12/2 and it works just fine.

Thank you for whatever help you are able to offer. I feel like I've run through all the troubleshooting I can.
Hineken you just told me what is wrong and you stated that the neutral wire attached to the GFCI breaker is terminated to the neutral bar but the neutral in your cable has to terminate on the breaker not the neutral bar. That’s why it’s tripping when you turn it on.
It would be nice to see a picture of your panel showing your GFCI breaker. One of two things are wrong. # 1 you have the breaker wired wrong or the breaker is no good, I’ve had to return several breakers that kept tripping
 
Wow, overwhelmed by all the rapid input. Thank you so much for helping me out.

All equipment and wiring is new. Could I check for a ground fault within the heater itself by simply running a continuity test from hot pigtail to ground screw (while it is not energized, of course)? Or am I oversimplifying?

I do have a 2nd GFCI breaker I can test but I'm waiting for the rain to subside before removing the cover on my service panel again. Installed a 2nd breaker & wiring at the same time as the first for a future heater in the 2nd bathroom. So I will swap the wire at the service panel and see.

The neutral in my cable is indeed terminated to the breaker, then the breaker pigtail (indicated by zig-zag line in sketch) in terminated on the bar. So I believe this is wired correctly. I can provide a photo to double check, again once the rain stops.

It seemed to me by testing the breaker with just an outlet with a load on it, that would prove the breaker is OK since it didn't trip? But now that I think about it, the load I applied didn't have a ground (duh). I will have to try that again but with a different load with a ground. Still boggles my mind that with the switch in the OFF position (in theory an open circuit) the breaker still popped when the heater was attached after the switch.

I did not draw in the service panel hot bars in my sketch, but the breaker is installed as usual such that it clips on to the hot bar, but perhaps I misunderstood the comment.

Thanks again, all.
 
I did not draw in the service panel hot bars in my sketch, but the breaker is installed as usual such that it clips on to the hot bar, but perhaps I misunderstood the comment.

that was my fault , being unfamiliar with American panels.
 
As we’ve said before, nothing wrong in the house wiring as it worked with a different appliance, which means it must be the heater.

you could try a resistance check but if your GFCI are as sensitive as our RCDs, you might need specialist test equipment to find a fault.
 
But was it still running through a gfci at the panel or a standard breaker.
 
I swapped the GFCI breaker with another GFCI breaker. Same behavior. It trips.

Connected a real grounded load (500W work light) to an outlet at the end of the circuit to test everything up to just before the heater. Worked fine.

I didn't understand why the breaker would trip if I had a switch on the hot line side turned to OFF. There should be no current flow to measure, right? So, just for testing purposes, I removed the ground from the switch temporarily (but the heater is still grounded back to the service panel). The breaker stayed on this time until I toggled the switch to ON. The heater fan just barely started then the breaker did its job and tripped.

@Paignton pete are you suggesting that since the neutrals and grounds are all bonded together at the service panel, if there is a ground fault in another circuit in my home, it could actually cause the GFCI breaker on the heater circuit to trip? I have numerous GFCI outlets on various circuits that behave OK currently, but no other GFCI breakers. Pardon my ignorance.

It seems, as @littlespark has suspected, there is a ground fault in the heater unit. I will contact the manufacturer to see if they are of any help. Is it possible that I'm not going to have any success using a GFCI breaker with the heater? That there is some innate characteristic of the wiring of the heater that it will always show a ground fault (albeit perhaps a "minor" one that is registered by the sensitive GFCI)? Or is this a bonified appliance defect? My now frustrated instinct is to just remove GFCI protection from the circuit, but that doesn't seem right. Or would it be just fine under normal use to not have GFCI protection? I'm sure the majority of these heaters are installed without GFCI protection and I don't see that the NEC requires it. Though I do work with building codes (structural engineer), so understand "code minimum" vs best practice.

See attached (2) photos of my service panel and the (2) GFCI breakers. The lower of the (2) breakers is the one in question. Hard to see with the long breaker bodies and pigtails in the way, but the neutrals are in fact attached to the breaker, then the pigtail to the bus bar.

Side question: I had this panel replaced a year ago by a professional (and the City inspected it). The electrician ran all the cables through a single large knockout (top right of photo) and removed the screw down portion of the cable clamp (but at least leaves a grommet of sorts). The cables are not attached to the wall framing except with a "lasso" of NM-B insulation sheath. The bundled length is less than 24" from top of panel to wall top plate after which they fan out somewhat. From what I can tell from reading the NEC, it seems only (9) current carrying conductors are allowed through a knockout, no matter the diameter and the cables should be clamped within 8" of the knockout. Is any/all of this not code compliant? Maybe the City was lenient in this case since they were removing an old Zinsco-Sylvania panel which are known to be fire hazards, thereby at least mitigating a known hazard.

Thanks again, all.
 

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