I have a 13 year old Sunbelt hot tub. it has a Gecko controller. I have replaced the main circuit board a few years back. I recently replaced main pump and blower. all was good. I then drain and cleaned tub. It had been sitting empty for a few weeks. Once refilled all seemed fine, when I checked next morning all was dead, nothing running, and no display on topside.
Circuit is fine, I am getting correct votalge across terminals, 120V from each hot to ground, and 240 across two hot terminals. All fuses are good, tested voltage across both ends. I pulled out board, but nothing obvious (when repalced board in the past, there were burn marks in proximity of relays). All capacitors look okay, nothing swollen or leaking. The transformer has 2 primary lead and 3 secondary (yellow, green, red). I measured resistance across primary, showed 56 OHMs, and from yellow to both green and orange, resistance was something like .6 and 1.5, I don't remember exact number, but close, going by memory, not always reliable. I pulled transformer plug and test voltage from post that feeds the white and black wires, got 120v to ground, 240 to hot line in.
So I am trying to determine if my board is bad, or possibly the transformer or topside controller. So I have a few fquestions:
Should the tub run with topside disconnected? If not how can I determine it is bad? Is there a way to jubp leads somehow to turn on tub?
Is there a way to further test the transformer?
Any help is appreciated.