Can you connect a direct vent hot water heater to a standard masonry chimney flue? Reason I ask -- my water heater has pretty much died so I need to purchase a new one. I also know that my chimney flue is soon in need of a re-lining -- so I was going to purchase a direct vent water heater since its cheaper then re-lining the chimney. I'd like to hook it up to the chimney flue temporarily because I'm in the middle of a kitchen remodel and don't have time to run the vent the way that I would like too, and I'm even considering moving the water heater location altogether once the kitcen is done. Wouldn't take me more then a couple hours to replace the old water heater if I can just hook it back up to the chimney flue and get by like that for a few weeks.

Is this a bad move?