Vito I replaced my tank with a new style from John Carrillo a couple of years ago, and after the install it would not fire. Igniter worked it was like it wasn't getting fuel. John was very helpful with my problem. Finally after numerous diagnostic procedures, We determined it was the fuel solenoid, I purchased Fuel Solenoid kit WPX 386650 from John and that solved my problem. Their is no correlation between changing the tank and the fuel system, just a coincidence solenoid stop working best I can figure. That was almost three years ago and AquaHot is still working fine today.