So I bought this used hot tub, it was wired for 120Vac. I brought it home, wired it up like I bought it for 120Vac, all worked fine on 120Vac. Jets were not working, but I will ask about that at the end of this initial question. I wired the system for 240Vac, did what it said, moved red wire, etc. Have panel mounted GFCI, previously working fine on the older tub I replaced. AC wiring is OK. I have electrical and electronic systems experience.
I have a 6600-086, Rev A PCB. The jumper for 1-2 was removed when I got the tub. It was supposed to be IN for 120Vac, and out for 240Vac. However, if you look at the tale in the manual Jumper 1-2 is for 120/240Vac 40A. So is this board OK at 120Vac with 1-2 removed? Anyway, now the GFCI trips immediately.
1. Through process of elimination I have found the Plug-in transformer is what is tripping the breaker. The transformer reads fine for resistance and to ground. I suspect that whatever the 12Vac power (rectifier, voltage regulator, etc) is causing a problem. The fuse that powers the transformer does not blow. With everything connected except the transformer, the GFCI is OK. With everything off the board, or taking things off one at a time the GFCI trips until I remove the transformer last. The 12Vac input to the board does not measure a short or short to ground.
2. Transformer reads resistance OK and is not shorted to case. Primary reads 19 Ohms, secondary, 0.5 Ohms. Isolate the transformer from case, still trips breaker. Cut the yellow wires (so not connected to PCB, trips breaker. Transformer disconnected, PCB primary pins read 40 Ohms to Ground on one side, Infinity on the other.
3. Heater measures OK. Checked all wiring, no nicks or cuts on insulation on all wires.
4. Could not find specific circuit board troubleshooting or schematic for the PCB. Looks like it has been replaced by another model 6600-0724. Best case, a $215 acquisition, so I would like to be sure before I order one.
Anybody want to share a schematic for that PCB?
Anybody have a suggestion for further troubleshooting?
