Have a 1985 Hot Springs Jetsetter. Got it used a year ago and replaced the heating element. Everything was working until I turned the heater down for a 1 week vacation. Got back and turned the heater up only to trip the GFCI. Whenever the heater is turned up it trips the GFCI. Anyone got a clue?

It sounds like it could be the element. Is your pH being balanced weekly? It doesn't take long for low pH to kill an element. It could also be a burnt wire in the control box or the heater plug itself.

Pete
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