reb78

I think there is a minor leak there as you say. The terminals are a bit crusty. I have cleaned them up, it heats fine (as in it will heat) but I cant get to the bottom of the OHH error.

Thanks for the reply. I have felt it all over and its as cool as the water in the tub, so i dont think its overheating. One other bit of info I forgot to mention above was that I tried it shortly after the error first appeared and it didnt seem to stop heating. I set the heat to 38C and it got to 41C and showed no sign of stopping heating. I initially thought sticky relay but it seems to click so presume it is switching. The OHH on startup come up before i think it calls the heater to heat even?

Hi folks, I am looking for a bit of help with a problem on our hot tub. It's old and we inherited it when we bought the house we now own. In the last year we have replaced the control panel, two speed pump, one of the one speed pumps and a fair bit of leaky pipework. It has functioned without problems for about 6 months! We went out the other night to use it and OHH was on the control panel. Pressing a button on the panel made it disappear and we were able to use it but it did return. I turned it off for the night and then went out the next day to take a look at it. There is some corrosion around the element connections and I am not sure if this is related. Flow with the circulation pump is good (this is a two speed pump that runs at the lower speed when circulating). The filters are clean (replaced them just in case) and the water level is all correct. Testing today. If I turn on the main supply to the tub, the start up process begins on the control screen it makes a noise a bit like an electric kettle as it is turned on and then the OHH error comes up on the main screen within about 30 secs of turning the tub on, just after the kettle noise. This is either before or just after the Pr code appears for priming. If left for a few seconds at this point, I can press the Pump 1 button and set the priming off. It then runs through the priming process, registers the temperature shortly afterwards (today it was 18.5C) then heats as normal. At this point today, I set the temp to 26C. It got there fine, but what happens next might help with diagnosis perhaps/hopefully! So, if I increase the temp, it continues to heat. I can hear the heater relay click in and out in time with the heat message on the control panel, so assume that isn’t sticking. If I then decrease the temp after it has started heating, the circ pump stops, I hear the noise like a kettle (presumably from the heater) and then the OHH message appears. Waiting a couple of minutes and then pressing the pump button allows it all to start up again. Not sure what to do next for diagnostics and I dont want to throw money at parts without knowing what the fault is. Any advice on where to go next very much appreciated! Current setup: