Pentair Mastertemp 400 - display not working

[JamesW]

Correct.

Did they both just suddenly stop reading correctly?

If yes, it is unusual for two to go out at the exact same time.

Try resetting the connections to see if it is just a connection problem.

 

[JamesW]

 

[JamesW]

 

[JamesW]

Unplug the black plug, redo the wire connections and then plug the plug back in.

 

[wsdivall]

The problem is the temperature reading.

The Automation won't turn on the heater if the reading is higher than the set point.

Replace the temperature sensors for air and water and then see if it works.

Thank you everyone for your assistance on this. So helpful and so fast. Problem fixed. I replaced both the water/air temp sensors and everything is working like new.

 

[wsdivall]

Unplug the black plug, redo the wire connections and then plug the plug back in.

View attachment 624540
View attachment 624544

Thanks for all the diagrams and pictures. This was so helpful as I am a visual learner. Water/Air Temp sensors replaced and all is good.

 

[JamesW]

TFP is a registered 501(c)3 non-profit that is maintained by user donations.

All of our content is free of advertisements.

Please consider donating at:

Become a TFP Supporter

Help Support TFP Trouble Free Pool is run by a dedicated group of volunteers that … Read more…

www.troublefreepool.com