Report "I have a 95% dayton that is in a counterflow apllication that I rotated the inducer to exit right. I had a pressure switch problem originally and did not have a manometer to check readings. I ordered both -.4 and -1.1 switches that took me better than a week to get. In the meantime I put clear hoses on each switch to watch for condensate and I put a U-tube on to monitor. The inducer port reads constant -1.8 WC and the trap port reads -.9 constant. I did have water in both line originally. I did not have a tee on the drain originally but I did have it in clear vynil and it always drained good but hindsight told me I need to tee the drain. So yesterday after double checking everything on the installation venting, burner manifold pressure, pressures at the trap the furnace ran perfect until 2:30 am Pressure switch lockout, fault code 3, checked the clear hose to the -.4 switch it was dry but that switch failed. I put a U-tube on the port during a retry and it was -.9 WC. Put the old switch back on and it works fine. After all that, Question: Are we having problems with the pressure switches, or once there is moisture in these switches are the unreliable. This is a relatively new installation, first season"