Couple more ?'s from a newb

[troyr_2000]

I have a flush mounted insert with rigid liner now. I am thinking about pulling it out 6-8" to get more radiant heat. Questions are will I gain enough heat to make it worth the work, and I will be putting a piece of flex on from the stove but does the flex have to be stainless or can it be galvanized?

 

[fossil]

No galvanized. Period. Rick

 

[troyr_2000]

If you don't mind me asking why no galvanized period? I'm just trying to learn here don't take this question the wrong way.

 

[fossil]

Temperatures and materials. The only place you'll find galvanized piping used in a solid fuel-burning appliance application is for the outer covering on double wall Class A chimney pipe. The inner piping in that chimney will be stainless steel. At the temperatures experienced from these things, galvanized single wall pipe would off-gas noxious vapors (notably zinc or compunds thereof). At least that's my rudimentary understanding of it. If I'm wrong, you can bet that I'll be pounced upon mercilessly any minute now. Rick

 

[Corey]

If you run galvanized pipe and the stove got hot enough - possibly during a very hot burn or during a flue fire - the zinc coating galvanized pipe will burn and emit zinc oxide fumes. Exposure to these fumes in significant concentration can lead to 'fume fever' - basically gives you flue like symptoms for a couple of days.

(broken link removed to http://files.aws.org/technical/facts/FACT-25.PDF)

 

[troyr_2000]

Great, then am I'm going to have to redo my entire liner? I couldn't get the damper out of the existing 12" chimney so I couldn't use any double walled or insulated pipe so I just put single walled galvanized down with the damper open the entire lenth. Are these fumes something you can smell?

 

[fossil]

Galvanized pipe is readily available for woodstove applications...that doesn't mean I'd use it. I'm just relating something I've learned by hanging around here. And here's a link to a comment from a professional:

https://www.hearth.com/econtent/index.php/wiki/Galvanized_stove_pipe_-_NO/

 

[Dune]

The link from fossil is a good start, but please be aware that metal fume fever can be fatal, and there is NO cure.

 

[yukiginger]

Do you have a blower on the insert, or does it not have the capability? This will make more difference than pulling it out.

MarkG

 

[troyr_2000]

I do have a blower, I just figured every little bit would help.

 

[yukiginger]

Okay, then my opinion is that the risk of screwing up your installation by messing with the insert is not offset by the potential gain of moving it out a bit.

MarkG