Spring startup has proven problematic with our heater, Pentair Mastertemp 250. When turned on and the temperature setting is set to 85, the temperature reading starts high, like 125, then slowly drops down till around 76. The heater then kicks in and starts, but instantly the reading spikes to 130 and the heater turns off again immediately. I am wondering what the issue might be? Seems like the thermistor is maybe receiving incorrect information and is maybe set up wrong. This is strange as this is a brand new pool build last year and it seemed to work okay then. This issue has only manifested this years start up. The pool equipment is also located indoors and there are no rodents anywhere to speak of, and the area is clean and easily accessible.
Pentair erratic temp readings
- Thread starter Ctone1975
- Start date
Do you have automation with a water temperature readout? If so, is that accurate? If it isn’t, your temperature sensor may have gone bad. A fast, easy, cheap fix.
agree it might be a sensor. I have three temp sensors, and one died after about 18 months. and the other two are going on eight years without any problems.