Sporadic GFI Breaker Trips on New Spa

[spacetanker]

Late last year we took delivery of an Artesian Kona Elite spa (2 5HP main pumps).  The spa was wired to a 50A GFI breaker disconnect in accordance with the dealers' instructions.  The disconnect was tied to a 60A breaker in the main panel.

We immediately ran into problems with the spa sporadically tripping the breaker,  Sometimes it was in the first 15 minute cycle, other times it would wait until the third 15 minute cycle.  Ordinarily we would bathe for about 30 minutes and wouldn't have any trouble.  On average it would trip every 3-4 weeks one way or the other.

The technicians were out numerous times.  Both main pumps were replaced.  The heater was replaced.  The circulation pump was replaced.  The pack was programmed to not run the heater when Pump #2 was energized.  None of these resolved the problem.  Ultimately we replaced the 50A GFI with a 60A GFI breaker (tied to a 70A breaker in the main panel) a little over a month ago

The higher amperage breaker was certainly helpful - and in hindsight probably should have been the FIRST corrective measure - but even with that change a few days ago the breaker tripped.  That said, at the point when it tripped the spa had been running continuously for about an hour.  The spa was unoccupied for the first 15 minute cycle, which we initiated with the cover open because the water was too hot (a filtration cycle issue, discussed separately).  We were in the spa for most of 3 cycles, and the spa tripped as the pumps were being turned off before we exited.

Given that information, I have a question about expectations.  The engineer in me wants to think that the design of the system should allow the spa to operate continuously, as it might be were it in a commercial setting (e.g., hotel setting with frequent bathers).  

(1)  Does anyone have any insight into what is reasonable to expect in terms of continuous operation with both pumps and the heater operating?  

(2)  The same question, if the heater wasn't energized while the pumps were running?  

(3)  Is a spa designed to only operate continuously for a certain period of time? 

Thank you!

[jeremyh]

Interesting, but I'll give it a shot. 1st breaker size should not have to be changed. Both breakers should be the same size. Proper wire needs to be used according to length of run. No splices or junction boxes. If there is a breaker/wiring issue the breaker may be warm to the touch when tripped.

If not that, I would look into an "over fill" or something with a small drip inside the spa dripping / leaking back on a component. If all spa equipment turns on and runs, typically it is not component related. Since it sounds most of the equipment was replaced you have other issues.

as far as your questions, the spa should run as long as you want, with the exception of pump timers, regardless of heater (assuming proper pack configuration, for amp draw)

[BoatersExchange]

I would be money that the supply wire is undersized or has a junction or defect.