Right. i would stay away from home depot, costco spas. As far as others like guys above mentioned... Most popular, Hotsprings(happy owner!), Tiger river, Caldera, Hot spot, Solana, D1, and sundance are my top choices.
You cant rebuild any of those heater unless, you start from scratch. And those relays are hard to find according to watkins techs, ive tried, but had to order new iq. But relays are out there, or something similar to them. Too bad you dont have iq2020, like chas said, just change out relay board. Oh, I did see a heater like yours on ebay, half the price. Good luck
So, it ended up being a tripped tco. lol.Btw Op, hate to say, but ive seen a couple of those heaters go up in flames. I would replace it. Good deal on trombone (tribend) heater on ebay right now. Good luck
You either have a bad relay board, bad thermistors, bad control head, bad pressure switch(if heater has one) or the neutral wire on wrong breaker. Was it working fine they way its wired before? Check relays any dark marks around them, sometimes you cant tell. You have to remove it.