Hello,
I have an unknown spa, but one year ago I replaced the heating unit with a Hydroquip CS500-A-15A(model #VOVABDA-1104E0). About 2 weeks ago, the heating unit kicked the breaked switch on the power cord off(not the GFI wall plug). If I turn the thermostat down to the lowest setting and reset the power cord switch, then the motor will power on. Once I start to turn up the thermostat, then the power cord breaker kicks off again. Any ideas on what part has gone bad, and if I could get a part name/number so I can order from the site.
Thanks for any help.
Bozy

Heater element most likely compromised, causing a ground fault, or the cord based gfi is going bad.

Thanks for the quick reply, So I quess the first step would be to cut off the inline breaker switch and attach a regular plug end. It will plug into a wall outlet with a GFI plug any way so it is still safe(was kind of redundent with two Breakers in a row).
If that doesn't solve the problem then should I order the thermostat part, or the actually heating element?
Thanks again,
Bozy

You have to eliminate the easy (and cheap) suspects first, before going further.

Replace plug end.

See if that solves it.

If it does then use tub.

If not, then go after possible heater problem.

Never purchase anything unless you either:
1. Know what's defective,
or
2. Are willing to keep replacing parts until it starts working...

If in doubt, ask more questions, figure out more stuff and go back to #1.