Your talking about a light fixture. This is going to a spa motor. Just a 20 amp circuit with a GFI mounted below the tub with access, is legal. My question is can I tap a 15 amp pool light circuit (if the motor calls for it, which I don't think it does, even though the spa company said it would) sharing the same circuit as the pool light if they were not going to be used at the same time. The pool light circuit has a switch controlling a GFI recept (Standard) than out to the light. I would tie into the line in at the switch and run underground to the spa, a short distance. The panel is on the other side of the house, making it really difficult the run the circuit.
Conclusion though is to run a new 20 amp GFI circuit from the panel and just charge for a much bigger job.
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