I'm selling my home and the city came to inspect the gas furnace since it was converted from oil to gas 10yrs ago without permit. Anyway, everything passed except the inspector said the bushing needed to be replaced. He couldn't answer any of my questions when I asked what he was talking about. What is a bushing? I've had 3 different estimates from plumbers as to what needed to be done to pass inspection and what they said needed to be done the inspector passed so they were trying to rip me off. I'm hoping my husband can change the bushing if we had a clue what it is or looks like. It's not what connects the gas lines together the looks like an elbow is it? Also if I had a plumber do this about how much would it be? Thank you.

Probably a bushing was installed in the gas line and many areas will not allow bushings on natural gas. You will have to replace with a black iron bell reducer. If you do not know what you are doing call a HVAC person who does.