infinity spa with 2 pumps and balboa pack and prozone ozonator spa was running properly for 3 months and then the breaker tripped, reset breaker and the tub primes but when the heater kicks in it trips again, replaced the spa pack and it does the same thing...this is the second breaker the tub has blown, the first one blow and would not send 240v to the tub, replaced breaker and worked fine up until now. Breaker manufacture has not had any recalls on breakers and these are the only 2 defective ones that have been returned, they claim it is the tub causing the problem. What would cause the breaker to blow instead of just trip?? GFI breaker is in the panel which is approx. 60-70ft away from the tub. Tub was not in use when the breaker tripped/blow, if anything it was in a filter cycle with the heater possibily on when this happened. Tub is new <6 months old. I have attached a picture of the breaker and it has actually blown apart near the bottom.

Ok I deleted the photo because it simply stated the obvious - and I couldn't tell any type of 'blowing apart' from the photo.

None of this makes sense - what you're saying about your spa and breaker combination.

To actually BLOW a breaker really requires a direct short - something that would be in the thousands of amps short circuit current.

Yes, I'm siding with the engineers on this one - something on the load side of your spa circuit breaker is causing the blow out.

What you need to do is be a little more detailed about the wire run from your breaker to the spa, everything... I mean you go from a tripped gfci breaker to a new controller to the 2nd breaker the tub has blown... are you kidding me?

Something is wrong with this installation, and it ain't your tub.

electricain check the breaker and it is ok, changed out spa pack and it still does the same thing, trips as soon as the heater atempts to kick in, the gfci breaker is in the panel and the wire runs to a switch and then into the hot tub. the wiring installation is done properly, the tub worked for 3 months before it tripped. i have unplugged everything, pumps, light and ozonator and everytime it trips when the heater wants to kick in, the only things i haven't tried is diconnecting the heater and trying to run the spa with a non gfi breaker.

When you say it's 'Blown', do you mean it is tripping the breaker?

not blown, the breaker trips everytime the heater atempts to kick in.

Ok that's an entirely different situation then. Yes, disconnect both legs of the heater and try again. It is quite possible to have a defective element even on a new controller - they're not really the most robust components ever produced - we sell them for 19.95 in quantities of 10 or more.

"Blown" as a term in this forum refers to 'burned out', or 'destroyed'.

ok now what, disconnected both heater legs and it still trips when it want to kick the heater in??

Ok well it's not really prudent to go further unless I can see -
1. A photo of the inside of the GFCI breaker box and the wiring going to it.
2. A photo of the inside of the remote cut-off box.
3. A photo of the inside of your Balboa control.