I have a ~year-old Jacuzzi J-385 hot tub and one day got the "watchdog" error message with dashes. Research showed likely source of problem was the water temperature sensor. Water temp was actually and nowhere near the high temps that watchdog is designed to prevent. So, I bought and installed a new sensor (6600-751 Sundance/Jacuzzi Temperature Sensor with 3 Pin Connector). Decided to drain the tub before repair since it had been a couple of weeks before the part came in and the water needed changing anyway. Sensor and new O-ring install was straightforward.
After re-filling tub, I turned the GFCI back on. Watchdog message was gone and temp measured 70-some deg which was in the right ballpark. But, a completely new set of error words came up: "Overheat GFCI Trip Call for Service"
After 4-5 minute of normal display and pump operation (except for the error message), the GFCI on the wall box trips. Checked for water leaks or loose wires inside the panel and found nothing amiss. After several cycles of the same behavior (GFCI trips every time after 4-5 mins after a reset), the GFCI breaker would not even reset. It would not pass electricity to the hot tub at all. I disconnected the wires to the tub at the breaker and still GFCI would not reset so definitely the GFCI had gone bad and not anything related to the tub or wiring to the tub. Not sure how it went bad since the GFCI worked (albeit with tub perhaps tripping it?) just before it went bad altogether.
So, had electrician put in a new GFCI breaker. Now the GFCI holds and power is restored to the hot tub. Messages on the display (Overheat GFCI trip call for service) are still there. I figured the breaker would trip again after the 4-5 minutes but this time, the tub stays on! Tub heats up to the set temp and jets work.
So, what was the problem that caused the GFCI to trip and the messages to appear? Why did the problem happen after a refill? Does the problem still persist and somehow the GFCI breaker isn't getting tripped as it was before? If there is no longer a problem, how do I get rid of the error messages? Or, is the presence of the messages an indication that there is still and equipment or sensor (perhaps the hi limit sensor) issue?
Thanks in advance!