Hot tub is older Cal Spa Eliminator series. Hot tub turns on and runs fine and heats for a few minutes then shuts down. After a few minutes rest, it starts itself back up and runs fine again for a few minutes then repeats the cycle. I had a technician out and he doesn't know the answer.
The winter freeze protection switch was on and I switched it back to the timer position. Doesn't make any difference. Water flow is good while running. The motor case does not seem to be too hot.