How do I light my water heater?

Jim my understanding off these 4 pages of posts is that the water heater runs for 45 mins continuously but does not get hot. If this is the case you can eliminate all the talk of gas valves, ingniter problems, EOC and thermostat problems. You also checked the water coming out of the relief vale and that was only luke warm after an 45 min run also. So that would eliminate any problems with the bypass valve or mixing valves not being in the right position. To me the only thing left would be the quality of the flame. Have you tried to adjust the air fuel mixture? I slide mine until it roars a bit then back off some. Without seeing or hearing the flame that is what I would suspect. Also you can remove the gas orifice and clean in alcohol to make sure it is fully open. A restriction to the burner tube would produce a small or low quality flame. My will produce hot water after 15 mins at 70 degrees. What is the outside temperature where you are now?