September 2004 discovered one night the water was a bit cool....found the GFCI plug tripped. Reset it and it immediately it reset again.

HotSprings service replaced the heating element, which fixed the problem, until late December 04. Same thing - cold water, GFCI tripped. HS replaced the element again. Jump ahead to March of 2005 - ditto. 3 new heating elements in 6 months. (Note: HS distributor continues to charge labor & trip charge, and I refuse to call them for more work.) I just shut the thing off this last April. Tonight, reset the GFCI on the plug, the pump worked fine, but just checked it, and again tripped 2 hours later.

Prior to initial problem last year, this little hot tub had been trouble free for 11 years.

I have pressed all reset buttons at one time or another during all this, and that did help for about 3 days, then tripped again.

The circulating pump will not run when GFCI is tripped, so not circulating anything.

I am at my wits end dealing with this, and I am looking for any insight as to what anyone thinks might be causing this.

Side note: the dedicated outlet was used by local HVAC contractor who plugged his giant duct sucking machine into it...that was late summer of 04. While I can't imagine that would have damaged anything, after I read a post about a similar GFCI tripping problem on this forum, I plan on replacing the breaker in the exterior service box. But aside form that, any suggestions are more than welcome!!

Other detaile: 115v unit; dedicated GFCI circuit outside, regular breaker inside service panel.

Thank you!

If you turn the heat knob all the way down, then try and re-set the GFCI, does it still trip?

When I turned it on tonight, the temp knob was nearly all the way off. I turned it to about the "1" (it goes up to "5"). But I'm not sure if the unit was already running when I did that or not. I will try it as you suggest and let you know the results.

Prior to al lthis, you would always hear a "click" when you would turn the temp knob (up or down) when it passed a certain temp; I always thought this was the heating element kicking on. FWIW, haven't heard that "click" since all this happened).

Thanks!

Just turned the temp knob all the way down, and pushed the GFCI reset, and it tripped immediately. Unplugged it, tried it again, and immediate reset.
(I swear, it's gotta be 5:00 somewhere....or it will be soon!)

If the t-stat is working properly, it's not the heater...

To be sure, you can un-plug the heater from the control box.... and try again. It's possible the t-stat is sticking (why you haven't heard that "click" which is indeed the heating relay kicking in) I think the heater receptacle might be a little tricky to get to, it may be tough to reach......plugging it back in will be the tough part- take note of the plug configuration when unplugging it... it will make plugging it back in much easier.

Be sure to close the eqqipment door after unplugging the heater (magnetic door intelock) before re-testing

Came home from work, and made sure the thermostat dial was all the way to the left - off. I unplugged the unit, reset the gfci, plugged it in and it fired right up, and it's been running fine - so far. (Fingers are crossed) No heat of course, but at least it hasn't kicked off. At least the sucker is running.

I haven't yet unplugged the heater as suggested, but if the spa continues to run tonight, I'm thinking we've ruled out the heating element as the culprit. Is that a logical assumption? Might this then be some kinf of thermostat issue?

Anyway, one step at a time. Thanks for your guidance.

Well, it tripped again. About 2 hours after it began working. Took off the back, reset the two red reset buttons (hot tub reset anf high temp reset). Unplugged the heater, reset the GFCI, and it immediately tripped again.

In checking the inside of the cabinet, the pump was very hot. Is that normal?

Something I neglected to mention earlier, back last September when they put in the 1st heating element, the claimed the reason it was shorting was the ozonator was bad. He removed it, and left the unit there, but what I thought was odd was he cut the powercord close to the unit. Rather than have it replaced, I opted to just go with a few more chemicals. Not sure if that information is helpful, but I just rememberd it.

Again, any insight appreciated.

I would find the source wires for the oxone and disconnect them, if even 1 strand of the power cord is shorted to one of the other lines it will trip the GFCI. The ozone will run during the "heat" cycle so it would trip during a heat cycle if the ozone cord is the reason.

Had the same problem and I ended up having a bad breaker. Costs around $100. Was the breaker in the GFCI panel.