Test Set up for Direct Vent Stove

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Ultralume

Member
Nov 1, 2020
16
Upstate New York
Is it possible to vent a DV stove by connecting the inner 4” exhaust to a b vent and leave the outer section open for drawing combustion air from the room? Not for permanent use just for testing..
 
How would you connect it?
How do you propose to get the air from
the outer pipe to the bottom of the stove where
the B-vent combustion air enters the unit?
 
Last edited:
Doing stuff like this is my job!

I will admit that I do this all the time, though I'm often connecting a 4" flex vent (via a coupler on the exhaust collar) into a full (wood) chimney. As I'm on a tall chimney, I normally have to restrict the air coming in (using roxul or foil tape to partially block the outer intake collar), as I get a huge amount of pull through the stack. For testing purposes this works to exhibit that the main components function. I cannot use this method to test units for issues that may be inherent to proper DV venting scenarios, such as excess sooting particularly with secondary air issues, or ghosting.

For a true test of operation using a DV set up is better, but for confirming function of the gas chain components it works well.
 
To answer the question :
How would you connect it?
This is how:
A673E797-5052-46EB-AADF-CE26EDBB8EAE.jpeg

I made a adapter to attach the exhaust port to a B vent pipe or a draft hood. Vermont Castings provided a detailed drawing in their manual of a draft restrictor plate to be used in tall chimneys. I made one as well if needed.

The stove already has an air intake manifold. Air should be able to enter the stove from the room by leaving the manifold open. The chimney draft should provide enough negative pressure to draw air into the stove.
It’s been very warm here in New York State so my testing will be postponed until it gets cold out..