I have a Pentair MasterTemp 250 heater for my spa. Last night I set the temp to 95 and waited a couple hours before going in. When I went in, the spa seemed quite hot. I got a thermometer and found that the water was 105 degrees. I went back to the heater and the readout said 95 and the heater was still going. Any ideas? Thermistor? Circuit board? Thanks
Overheating
- Thread starter mplsdon
- Start date
- Jul 21, 2013
- 65,185
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Most likely the thermistor on the heater manifold.
You can test the thermistor using a multimeter and measure the ohms which indicate the temperature it is reporting.
www.troublefreepool.com
You can test the thermistor using a multimeter and measure the ohms which indicate the temperature it is reporting.
Temperature Sensors - Further Reading
www.troublefreepool.com