Vent Pipe inside a framed chaise... Can I run the 3 inch pipe inside a 6in pipe thats already there?

[AC_150]

First post on the site so take it easy on me

I'm replacing my Lennox Propane Fireplace with a Quadra Fire Castile. The vent pipe from the propane fireplace is a 6 inch exhaust pipe and I was wondering what everyone's thoughts are on just running the 3in vent pipe for the pellet insert inside the 6 inch pipe. This is a wood framed chimney chaise.


Looking for some guidance and thoughts on this. Thanks!

 

[mikkeeh]

Can’t see any problems.

 

[Ssyko]

don't see why that wouldn't be fine. maybe adapt new pellet vent to your 6" existing with an adapter.

 

[johneh]

Like Ssyko said why not adapt to the 6 inch ?

 

[AC_150]

Would I need to do anything additional or just get a 3 to 6 transition adapter and there should be no other issue in terms of required clearances?

 

[johneh]

Just make sure the 6 in. is clean

 

[Highbeam]

Careful guys, we're not talking about a 6" class A flue for solid fuel but maybe a b-vent.

 

[AC_150]

What should I check to make sure the pipe is appropriately rated? I haven’t pulled the propane stove out yet but once I do I will verify that it’s the right quality and grade for safety. It vents through the roof, not sure if it’s single or double walled.

 

[mikkeeh]

If it was venting a propane heater, it’s probably a “b” vent....in which case it’s not appropriate for venting pellet appliances. You could however, run pellet vent inside it.

 

[Highbeam]

If it was venting a propane heater, it’s probably a “b” vent....in which case it’s not appropriate for venting pellet appliances. You could however, run pellet vent inside it.

Even then, I would worry about maintaining minumum clearance to combustibles. Bvent can be pretty close to combustibles and if the pellet vent is laying against the bvent.

 

[AC_150]

Sorry I've been busy but we have removed the gas fire place it the pipe is a 3 inch inside of a 6 inch. This should be fine for running the pellet stove?

Pics aren't the best but this is what it looks like.

Existing gas pipe 1

• AC_150
• Mar 9, 2019

Existing gas pipe

• AC_150
• Mar 9, 2019

Existing gas pipe 2

• AC_150
• Mar 9, 2019

 

[jerrieric]

Why not just put through the vent free in pellets through your 6 in? Seems like the 6-inch would just be like installing a thimble

 

[fmsm]

Call your local inspector, if the pipe is not rated for pellet fuel and there is an issue in the future you could be SOL with your insurance company. Also, what is your EVL? You may need 4 inch. Are you doing outside air? All in all your best bet may be to pull a pipe in that can do both while removing the original.

 

[railfanron]

There's no way that's a class a chimney and using it for a pellet stove could be a disaster. I would look into pulling the smaller pipe out of the 6 inch and then running an insulated class a flex chimney up the inside. This should solve any clearance issues.
Ron

 

[johneh]

I would vent it into the class A chimney using a 6 to 3 or 4
adapter that is if it is a class A chimney . my pipe goes from a 4 to 6
into a class A chimney and I have used it for 18 years with out a
problem