Question: I have a vermont castings "Radiance" gas stove, converted to LP fuel and installed in my basement. A b-vent is used, and it is routed approximately 35 feet up through a 4" flue liner on an existing outside masonry chimney. A rain cap was placed on top. My problem is that a strong odor and carbon monoxide (detected by a digital plug in device) accumulate after a few days of running only the pilot light. I can also detect flow reversal (cold air) when this occurs. The propane company has checked for leaks and says all is well. I would like to know if this particular model requires a proper vent for the pilot light alone or is this problem indicative of a problem with the specs of the pilot light. The odor that exists is not subtle. Also, please note that when the unit is functioning at full capacity, I have no odor or CO detection, and the flame pattern is excellent. Also, the unit seems to vent properly when the burner(s) are on. The trouble occurs, apparently, with only the pilot light running. What are your thoughts and suggestions? Thanks Answer: It appears that you have the problem figured out. The chimney is reversing when it is cold (stove not in use) and this is causing the pilot to vent into the home. In some cases, this pilot is very small, and the odor not detectable. However, LP is dirtier than natural gas, and this stove may also have a larger pilot than some others. The gas valve probably has an adjustment on the pilot. Make certain that it is not turned up too high...that is, it may still function well at a lower setting. Make certain that the proper orifices were installed when the conversion was done - I think there would be two different orifices, one for the pilot and one for the gas valve. The reversing chimney could be tougher to solve. Make certain that there is plenty of combustion air in the basement. It make also be possible to add a "draft increasing " chimney cap to the B-Vent liner.. As a last resort, you might want to turn off the pilot light when the stove is not in use.