The thermister inside the sensor is kaput. Replacing it isn't hard.

Scott

Can this part be picked up at any dealer? Is it the cord and the device that is drilled into the pipe?

Pentair temp sensor for the Easytouch and Intellitouch is part number 520272. The older Compool models have a different part number, so be specific if you order one.

The 520272 has a 20' wire for installing inline in the return line. The air temp sensor has a much shorter wire and wouldnt work, wont reach your plumbing.

Just route the new sensor like the old, its a simple two pin connection to the pc board. On the other end, install it like the old (band clamp it to the return line)

Be sure to stay in the low voltage raceway inside the box (along the leftside), or hire an electrician if you are unsure!

Thank you! The cheapest I found was 37.95 and this company is local for me so no shipping charge. I only need about 6' of wire. I wonder if cutting the extra 15' would change the calibration?

Here is a link that might be useful: 520272 Pentair Sensor

You can cut it, wont hurt anything.
I have run them at many different lengths.

But its just as easy to zip tie the excess inside the low voltage raceway.