1997 Hot Spring Prodigy 110 V
Worked fine when I drained it last year....but after refill this year....

When I turn on the heater the house GFCI breaker goes off. Everything works fine until I turn the temp on. I'm guessing it's the element. Am I on the right track? How do I get to the heater out to replace the element or complete assembly, if needed? It seems to be tucked in there pretty tight. Is there anyone who knows how to do this or where to go to find out. I prefer not to pay someone else to do this!

Sounds like a heater to me. i just replaced one in a 1991 hotspring jetsetter. not sure how yours is set up.i drained the tub, loosened the clamp holding the heater housing and carefully moved the housing around to give me better access to the 4 bolts attaching the heater plate to the housing. remove the bolts, pull out the element, paying attention to how the gaskets are placed, then install the element, gaskets and bolts in reverse order.