Co axial insert adaptor for direct vent

[S15508g]

So I’m new here .
I have a old gas insert that has the two 3 inch holes on top exhaust and intake.
i had my chimney taken down to increase space in my attic as I’m converting it to a living space
My thought was to run a direct vent up the old chimney flute and out the side wall. I know there are adaptors that take a direct vent to two pipes. But is there an adaptor that will take two and then into the direct vent. It may even be that same adaptor just reverse it. But that seems to simple.

 

[DAKSY]

It IS that simple. I've reversed & used the adapter that way a number of times.
However, depending on the inside dimensions of your chimney, you
may have issues trying to vent thru to the outside...

 

[S15508g]

It IS that simple. I've reversed & used the adapter that way a number of times.
However, depending on the inside dimensions of your chimney, you
may have issues trying to vent thru to the outside...

View attachment 278615

What’s the smalles

 

[S15508g]

Ya. I agree. What’s the smallest direct vent pipe you’ve seen.

 

[DAKSY]

6-5/8" OD. That will fit the adapter.

 

[S15508g]

6-5/8" OD. That will fit the adapter.

Here’s an idea what if I run the two individual 3 inch tubes up the fireplace and then put the adaptor in at the top and then run my direct vent from that. As long as I have some clearance at the top that should work

 

[DAKSY]

That should work. Make sure that you have the correct co-linear flexible liners.
Many units require a stainless steel section directly off the exhaust side for 4 - 5 feet,
then switch to aluminum.