I replaced the motor and pump on a 1988 sundance supralounger. The tech turned the heat knob all the way up to heat the water when he was done. The water will now just barely make it to 100 degrees no matter how high the control knob is turned. It seems to be maintaining temperature but not increasing. We had no problem with the heater prior to the repair. The next tech sent first said the filter was dirty - I had just replaced it - it was brand new- only in a week! Then he said he wanted to replace the side control and temp sensor for a cost of 550.00 - I just replaced those things 2 years ago! I sent him home. Any advice? All I want is 2 more degrees!

Does the topside control indicate that the tub is at the temperature you have it set to? If so, then I would just replace the temp sensor. Might be a worth while moment to take the cover off the control cabinet (power off of course) and double check all the push on connectors. If one is dirty or loose, it will cause a false resistance reading, thus telling the computer the wrong temperature.

Hi - Thanks for the advice. I checked the control panel and one connection was loose but that did not resolve the problem. The topside control is a dial - no digital readout. I actually have the dial position at a higher level - top of the orange but not in the red zone- than I did last year to get the 102 degree temp we like. Also- when I was looking at the control panel I noticed that the red button on the heater had popped out. I reset it but still no additional heat when the dial is turned. Why would the high limit switch pop when the water is 99-100 degrees? Thanks for your help!

My apologies for misreading your year of manufacturer, was thinking of a 98 for some reason. Was thinking you had digital control. Moving on...

Can you determine if the high limit is still kicking out at that temperature? I have seen mechanical high temp breakers like that get weak, often due to an overheat condition, and sometimes just sheer age. They are adjustable, using an allen (hex) wrench but it is a little tricky to get at that screw. You could also just replace that breaker, if it is still kicking out at that temperature. It's basically a non-resetable and (supposed to be) a non adjustable thermostat, but you can adjust it. Proper adjustment is around 125 degrees.