Recently I smelt gas near my hallway furnace closet.
After examining the piping I noticed all the connections from the wall up to about one foot from the furnace were obviously pipe dope sealed leaving an almost coated appearance to the joint. But that last steel pipe nipple with reducer entering the furnace and connecting to the flex tubing inside the furnace had no such appearance.
My neighbor advised me to cut off the gas at the closest point to the furnace and disconnect those pipes that appeared to have not been pipe doped. Then, let the gas clear for a time and reconnect the line using pipe dope plus replace the flex line just to be safe. I went to a local home improvement store for parts and they explained to me that I did not need to dope the brass connectors on the ends connecting to the flex line ( brass to brass seals itself ) they also said never use thread tape at these points.
I got the line back together and there is no more gas smell!
My questions are, Did I do the right thing by not putting pipe dope on the brass fittings at the points where they connect to the flex line on both ends coming from the steal pipe and into the gas valve? Why should thread tape not be used here?
Chris
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