On 9/7/2013 9:22 PM, Mikepier wrote:
I have a 75 gal water heater with a 4 " vent going into a chimney. If I wanted to add a second water heater, what would be the proper way to vent both into the same pipe? Could I just add a Y and vent both through the same pipe going into the chimney?

Reason I wanted to add a second water heater is that this is a multi-family house and I wanted to split the demand for HW by zoning off the apts with 2 water heaters
By the way, my steam boiler vents into the chimney from the opposite side with its own separate vent pipe.


Check local codes., Many require a separate stack for each device. An
alternative is a high efficient unit that just uses a pvc vent