Welcome! Here are the website rules, as well as some tips for using this forum.
If you've found help here, check back in to let us know how everything worked out.
It's a great way to thank those who helped you.
I am involved in a furnace replacement and tune up for energy efficiency program. The program has a standard that the CO level in the flue gas has to be lower than 100 ppm. I have a Rheem furnace that I can't seem to get lower than 130 ppm any ideas? The furnace is only 2 years old and if it does not pass it will have to be replaced. I already lowered the manifold gas pressure to 3" water column and I do not want to get that any lower than that. It is a single stage, two pipe direct vent system using approx. 12' intake and 12' exhaust through 2" sch 40 pipe.