Using B Vent for DV Flue Pipe

[MfgEng]

I have an existing B-Vent fireplace installation that I would like to upgrade to a more efficient DV fireplace. The fireplace is mounted on in interior wall, and based on the structure (framing, location of doors and windows, etc) I cannot add a DV chase to vent horizontally. In order to replace the B-Vent with a DV pipe, a new chase would be required through a bedroom on the second floor, which I would really like to avoid at all costs.

I've read about co-linear vent piping for DV setups, but these seem to be rated for runs through non-combustible surfaces (such as masonry chimneys). I haven't found something explicitly stating that, or indicating the minimum distance from combustible surfaces from those pipes.

My original idea was to use a co-linear adapter to split the air intake from the exhaust flue, where I can easily run the 3" flex through a stud wall on the second floor and into the attic for air intake. The 3" exhaust would then be connected to the existing B Vent.

I can't find anywhere if this would be acceptable, and if not why? I've picked out the Regency P36 because it will fit, but can't find an estimated flue gas temperature, or even if this is an appliance category I (I'm assuming that it is). DV and B Vent pipes are both lined with aluminum pipe, which does not indicate to me either is designed for excessive condensation (indicating a category II or IV appliance).

Would love to hear some thoughts on this subject...

 

[DAKSY]

You can only use the venting that is approved for the appliance.
That venting was approved after extensive testing in a controlled environment.
You can't find information on doing it your way, because is has not been tested your way.
If something happens due to an incorrect install, the liability is YOURS & yours alone.
Do yourself a favor & install it in an approved manner. Your family will be safer for it.

 

[danimal1968]

You can only use the venting that is approved for the appliance.
That venting was approved after extensive testing in a controlled environment.
You can't find information on doing it your way, because is has not been tested your way.
If something happens due to an incorrect install, the liability is YOURS & yours alone.
Do yourself a favor & install it in an approved manner. Your family will be safer for it.

And if something bad were to happen, your homeowner's insurance won't have an easy way out of paying to repair or replace your home.

 

[Fsappo]

man, what on earth would make you not want to replace the b vent with direct vent? Maybe if you let us know why you are doing this we can find you a way to do it right?