Ok so I have an RH 35 in a rental unit Recently it has been giving problems. Background: The unit is on the 2nd floor and vents into the chimney flue. the building is circa 1900 and flue is not lined. In the basement there is a 30000 btu gas furnace that heats the first floor and 2 water heaters that all go into the chimney. I made sure everything is sealed tight with chimney cement. I put a match to the back to the space heater and the flame gets sucked into the chimney so I am getting good draft I believe. There was an older space heater in this unit with no spill switch before I replaced with this one in 2009. There are 2 carbon monoxide detectors in the room with this unit that have not registered any CO ever. First I jumped the spill switch and the thing was running good. Then I hooked the switch back up and it would blow out. I think it was getting too hot (too much gas pressure) so I had a gas valve installed. Replaced the spill switch limit. Replaced the fan limit. It ran good for a few weeks, no complaints from tenant. And there was a huge difference in the heat that was coming from it due to the reduction in gas pressure. Now it starts going out again. So I Replaced the thermo couple. Still blows out. It runs for a while then goes out. Its been windy could that do it? Do you think I need to adjust the pilot flame since I reduced the gas pressure? It doesn't really go past the thermocouple like it should. If the pilot flame is too small would I be able to get it running like I can and then it blows out after a while? Or do you think I'm still having spill switch issues? How do I adjust the pilot flame?