Iinnai tankless waterheater worked at first but now just barely warms water

[Jim Brokenbourgh]

Newly installed Rinnai tankless water heater V65e worked at first for a few days but now just barely warms water and will not display codes. what should I do now?

 

[fitter30]

Have u rechecked the setpoints? Priority light come on with water running? If heater loses power before 6 hours of being powered up temp resets to 104*