If it is anything like my installation you are going to need the big vent
all the way to the top. Tankless water heaters crank out a lot of BTU's so
they need a large pipe to vent them. Look at the installation instructions
that came with your unit for the proper size of the vent.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.


"Jimmy" wrote in message
ps.com...
I recently purchased a Takagi TK1S, I am preparing to have this
installed soon. My question is this: my existing tank (located in my
basement) has 3" exhaust that goes into the chiminey stack, can the
new venting replace this? Does the venting only need to enter the
stack or does it need to be piped all the way to the roof? I hope
this makes sense. I have a couple photos if that will help,
unfortunately I cannot post them here, so I will email if needed.
Thank you.


-Jimmy