Furnace / water heater venting

[Bruce Hutton]

Furnace / water heater venting

The piping at the right is the furnace flue piping the one at the left is the water heater flue vent piping. These are running into a liner pipe that is installed in the chimney.

Is this acceptable for venting...shouldnt the smaller piping be vented above the larger piping & not Y'd together?
Couldnt this cause a backdrafting issue?

What are your thoughts?
Any guidance would be appreciated.
(I do have issues with the rusting as well)

Thanks in advance
Bruce

[Garry Sorrells]

Thee appears (hard to tell) to be an old furnace port to the chimney that has been sealed.
If that is the case then when a new furnace was installed that had a different height for discharge, the H2O heater port for the chimney was used (probably enlarged also).

There is a pesky notion that the H2O heater should be installed above the furnace as they enter the chimney.

Also, if you might use the view that the H2O heater is entering the flue above the furnace and thus is at a height above the furnace discharge head and thus meets that requirement. Though the angels of the pipe look low.

[Daniel Gailey]

i was taught & always told that the water heater pipe (smaller) needs to be above the furnace flue pipe

[Garry Sorrells]

i was taught & always told that the water heater pipe (smaller) needs to be above the furnace flue pipe

The H2O is above the furnanance but befor the chimney.

[Bob Harper]

The code contradicts itself. In one place, it states for the smaller input appliance to breech the chimney above the larger. Elsewhere, it allows manifolding before the chimney breeching.

The liner appears to be a little lower than either vent connector. Why is so much of the liner exposed? Is it not mortared into place?

If this is an aluminum liner, it, too will be corroded some. Should get a level II followed by combustion analysis. Is the furnace a fan assisted 80%'er?

[David Bell]

The wye they used appears to have crimped ends facing the equipment which could lead to flue gasses escaping and could explain the rusting at the connection points. Probably not of correct gauge for use as a flue connector. Also appears that B-vent is being used to connect the furnace and is also installed in reverse of proper flow.