ChainsawDR

Thanks for the reply. No I don't have a multimeter unfortunately. I could get one but I think the task at hand is crossing into a realm beyond my skillset and more suited to an experienced hand (I suspect its either the pump motor or voltage causing the problem). I'll bite the bullet and pay for an experienced service engineer to come over and work on it - it'll make me feel a lot more comfortable as I'm sitting in the bucket of water knowing that a pro evaluated the potential electricity issues! Thanks for the help, it's really appreciated! Once they've been in I'll loop back to update this thread with the final conclusion in case it helps anyone with a similar issue in future.

Thanks for all of the replies. Took the panel cover off to start taking a look at how to replace the O-rings at the ends of the heater unions (found a video on Youtube now) and decided to unplug the other heater wires (@Cusser hopefully these were what you meant) and turn it back on again with the pump plugged in. Was on for ~30secs then tripped - caught the moment on video and can see the flash coming from the plug connection (attaching 6 sec video clip of it tripping). Before replacing the O-rings, would the spark at the plug signal that there's a problem with the pump, or could that still be related to the O-rings (which didn't leak btw as the pump tripped when it tried to get going)? The connection from the pump to the motherboard looks like it has a burn mark on it (image attached). Also, the screw for the gasket looks to be on the far side with so space to get behind to unscrew it. Will watch some youtube videos first to see if there's a special technique or tool to removing (but if obviously non-standard to anyone please let me know - at the point of paying for someone to come out and service it) Thanks again for the help! ChainsawDR screw 'round the back side'? 6 sec video with spark from pump connection when it trips: IMG-4461.mov

LMFAO

Moved into a new home that has a Clearwater Spa. Power was off. Turned it on and the spa heated to full temp, great! Turned off, drained, cleaned, refilled, turned on - GFCI trips, dang! An electrician replaced the dated GFCI, but it still trips so must be a problem with the spa itself. I took off the spa electric panel box and started disconnecting/reconnecting pieces to try and debug/understand what was causing the GFCI to trip. I disconnected the heater and it ran ok without tripping the GFCI, but when the pump came on a small amount of water started dripping from both ends of the heater tube so I turned it off pronto. I then disconnected the pump as well as the heater and the power stayed on without tripping the GFCI. So to recap, with BOTH the Heater & Pump off, the GFCI does not trip. Strangely, although I'm 100% confident it ran with the heater off/pump on (the water leaked and it scared me), when I have this same heater-off/pump-on setup in place the GFCI trips again. Similarly having the heater-on/pump-off trips the GFCI. It feels odd that it worked fully before a drain and refill, and now there are maybe TWO things going wrong? Maybe I messed something up after draining and refilling? I've attached a second image of the gate valve that I haven't engaged at any point (for any testing or draining) and wondering if that was a mistake I've made? Is leaking water from the heater normal when the pump is on but heater disengaged? Thanks in advance for any help! ChainsawDR