I have a rheem 90 plus series model number rgfd07emcks over temp limit error 33, right when the unit starts up cold it flashes code 33 over temp limit. I have used the volt meter took it all the way to the board. I could not find an open anywhere. I then jumpered the whole circuit at the board still got the same code. I figured it was a bad logic board so I changed out the board however still have the same error code. '
Does anyone have any ideas