I bought a used 2004 Caldera Hawaiian hot tub earlier this year. It needed some work but I got it for $250 so I figured I'd take a flyer on it. Out of the gate I knew it needed a new heating unit, filter, pillows and a couple of valves replaced. I got all that taken care of, got an electrician out to run power to it and turned it on.
It ran through the start up and after that you could hear the burbling of the ozonator and see the bubbles coming up. We had nice hot water 24 hours later.. Everything on it has worked well for the last 5 months. Now I've been having issues with the circulation pump (the black one, not the blue) cutting out. First time it happened I pulled the filter and cleaned it, turned off the power to reset and when it came back on without the filter in the flashing temp error cleared. Put the new clean filter in place and since then it seems to have trouble keeping the circulation pump running and the temperature up. Sometimes I get the flashing temp, sometime the four dashes. I've checked for air lock and have done two water changes in the last six months. I always refill according to the manufacturers' direction.
Last time I had the flashing temp, I pulled the pressure switch cable off the circuit board and jumpered the pins and the error cleared. This makes me think my circuit board is not the problem. Turning the power off and back on occasionally clears the error. Sometimes it goes away on it's own after a number of hours. I also pulled the circulating pump and checked to make sure it wasn't clogged and it looked pretty clean. It will run sometimes for days with no problems, then other times it won't heat for a day or two, but resolves on it's own.
The new heating unit has the pressure switch inside the unit, unlike the original heater with the external pressure switch.
So after all that background the question is, do I have a bad pressure switch, hi-limit sensor, bad circulating pump or intermittent circuit board problems? I guess the other possibility is some blockage elsewhere, but when I pull a hose off the heater output it flows nicely, I don't want to start swapping out parts willy-nilly since the circulating pump alone is pushing $200 and the pressure switch looks to be integrated in the housing now.
Any ideas how to isolate the exact problem, or should I just break down and get a spa tech out here?
Thanks for any advice.
