hayward heater

Hi TFP Community, I’m experiencing issues with my Hayward H250FDN pool heater (Natural Gas). Despite replacing the igniter, flame sensor, control board, gas valve, and gas pressure regulator (adjusted with a manometer), the IF code has returned after a year. The heater turns on for 1-3 minutes...

My heater is showing the code EC( vs typical CE for comm. error). I have the display from insync engineering vs the hatward display. After a couple of minutes, it momentarily flashes 1.88 before going back to EC. I can't find anything related to this error code. What could the issue be?

I have an Hayward Omnilogic Panel and shows me that the temperature of my spa is at 80F when the water feels at 100F and I can confirm it by looking at the screen of the heater that the water is at 100F what I did was replace the temperature sensor but it still gave me the same problem, panel...