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joejenkins
venting furnace and water heater

Would it be possible, feasible, practical, permissible to vent a propane water heater into the same exhaust vent as an oil fired furnace?

baseball boy
Re: venting furnace and water heater

I just bought a Bosch liquid propane water heater -- tankless -- and on the outside of the box in very large letters in several different places it specifically states that it may NOT be dual vented. The traditional hot water heater I just removed was dual vented with my HVAC system for many years without any problems. Apparently the tankless system runs at a very high heat and needs its own vent... All I know is $995 for the water heater and $440 for the venting pipes (about 18 feet) -- hope it pays off in the long run! Hope this helps.

bp21901
Re: venting furnace and water heater

Generally on traditional style units, the water heater needs a smaller diameter flue than a furnace to have a sufficient draft. If the flue pipe is too large for the wh, a downdraft could occur and the exhaust may not make it out of the house.

canuk
Re: venting furnace and water heater
joejenkins wrote:

Would it be possible, feasible, practical, permissible to vent a propane water heater into the same exhaust vent as an oil fired furnace?

This answer would definitively be answered by your local municipal building inspections department.

There are some things that really aren't a DIY project .... unless your experienced and very knowledgeable .... and hooking up gas connections and exhaust venting for combustion appliances is one of those.

Just a thought. :)

joejenkins
Re: venting furnace and water heater

Thanks for the response. I believe the requirement to have a building inspector OK the set-up is proper, although my system is vented that way now, and it passed inspection. The idea of venting a tankless water heater is apparently different than a regular tank heater, so I guess the answer is "No, a tankless must be vented separately!" OK, I can live with that, and thanks again.

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