Replaced control panel and membrane pad and the heater now works. However it will heat for a while then stop and the service heater light will come on then it will go off and start heating again but it won’t go above 97 degrees or so. Any ideas how to fix?
Hi I would check both your Thermister or Thermal Regulator. Below are links to both parts…
Pentair Mastertemp Thermal Regulator Kit
Here are two really good videos we ran across about replacing and troubleshooting each of these parts.
Also do these things have a filter that needs to be changed or cleaned and if so how do you do it and could that be a possible cause?
I’m not aware of a specific filter for these parts, the biggest thing is keeping good overall pool chemistry as imbalanced pool water can be quite corrosive to these parts.
I’ve seen it mentioned descale. Is there a good way to do this?
Replaced both of these parts. Still heats up to a certain point. Think I got to 100 then service heater light comes on for a bit. Heater doesn’t heat while on then light goes off and it fires back up. Continuous cycle.