It was almost time for my new roof to go up, so I had an HVAC technician come out and service my rooftop AC unit plus the furnace in my house. Very thorough, chatted a lot, explaining things. We talked about my gas tank water heater too, since it is 26 years old and had a leak. I’m planning to replace it after my new roof goes up. The guy leaves. Let’s assume everything is looking good at this point.

The next week my new roof goes up, all good, no issues.

A week later it’s time to deal with the gas water heater. The contractor from the water heater company comes out to give an estimate and immediately discovers the gas water heater’s exhaust vent pipe had been disturbed - elevated by a full 12-14” and was allowing combustion gases to vent into the house (our water heater is in a closet off thr dining room). He also notices the furnace’s exhaust vent pipe has shifted upward (the furnace is also in the closet - it’s a big closet of 135 cubic feet), partially separating it from its connection.…