Hello from Palm Coast, Florida

It's a bad temperature sensor in the cell.

You have a non-Hayward cell. If it is under warranty then make a warranty claim on it from wherever you got it.

You can post the diagnostic information:

• Report all readings when you..
  • Move the switch from auto to off and check all of the readings.
  • Move the switch back to auto and recheck the readings.
  • Move the switch to off for a minute and then back to auto and recheck the readings.
• What is the actual salinity and how are you measuring it?

@JamesW thoughts?

Probably a defective cell. I would send it back for a warranty replacement.

The Hayward cell plug and cord are wired like this:

Holding the plug vertically with the cord going down and looking at the connection points. 1 is top left, 2 is top right, 3 is second down left and so on with 9 being lower left and 10 being lower right.

1) Black - Power to cell
2) White - Power to cell
3) Black - Power to cell
4) White - Power to cell
5) Brown - Not used
6) Red - Goes to thermistor
7) Orange - Not used
8) Yellow - Not used
9) Green - Not used
10) Blue - Goes to thermistor.

You can check the resistance from point 6 to point 10 to measure the resistance and compare to a 10k thermistor chart.


If you cut into the cord and wire in an external temperature sensor to the red and blue wires, that should work. I don’t know if the generic cord has the same color wires. So, you need to verify that the wires are the thermistor wires before you do anything.

You can use the Hayward GLX-PC-12-KIT 10K Thermistor Temperature Sensor with 15-Feet Cable as the external temperature sensor or the Pentair or Jandy equivalent temperature sensor.

Note: I am not recommending or suggesting that you do this. This modification is probably not acceptable to the cell or box manufacturer.

Only do what you know you can do safely.

Do at your own risk.