how long will it last?

[mckishen]

Greetings everyone, new to the boards, and I have some questions/concerns...

I've got a late sixties Pine Barren Stove that's approximately 3'Lx2'Hx2'W with a 6" top mount flue. It was part of a forced air heating system (totally enclosed in galvanized sheet metal, squirrel cage fan, the works), and I tore it all apart because it was worn out and hadn't been used in decades. It's located in my basement and last year I piped it to the chimney with two 6" black elbows and a 4' section of black pipe. I had terrible back puffing and a poor burn efficiency so I made some changes. I moved it closer to the wall (and sheathed it with corrugated sheet metal) and lined the interior of my 9" square chimney with the left over 6" galvanized duct. Coming off the flue I've a clean out, a trimmed section of black pipe going through the wall, and a black elbow at the base of the chimney (al 6") before the 6" galvanized chimney liner ties into the elbow. Everything seems to be working fine, but I'm concerned about the longevity of the 6" galvanized duct I used to line my chimney. It's pretty thin stuff and I'm mainly concerned with it deteriorating and having to fish it all out of the chimney later on down the road.

I've attached a sketch to better explain...

https://lh5.googleusercontent.com/-PtesrdyOvZ0/TrAgfSwThcI/AAAAAAAACyY/J9OP7yfBQQ0/s800/pine%2520barren.jpg

 

[lanternman]

is the galvanize duct like the stuff that you can get at home depot for heating duct? the thin snap together stuff?

 

[mckishen]

no, it's old duct that was installed way back before my time in the late sixties. not as thick a gauge as the black stove pipe, but in good shape. i used it to decrease the volume that my exhast has to travel vertically up the chimney, as well as decrease the amount of heat that was being transfered to the cmu/brick chimney wall. I figured, increase the velocity of the smoke and it'll have less time to cool and stick to the chimney wall, and the 6" duct is easier to clean.

 

[Dune]

is the galvanize duct like the stuff that you can get at home depot for heating duct? the thin snap together stuff?

Yes. It may be a gauge or two thicker, but that is what he is talking about.

 

[Dune]

no, it's old duct that was installed way back before my time in the late sixties. not as thick a gauge as the black stove pipe, but in good shape. i used it to decrease the volume that my exhast has to travel vertically up the chimney, as well as decrease the amount of heat that was being transfered to the cmu/brick chimney wall. I figured, increase the velocity of the smoke and it'll have less time to cool and stick to the chimney wall, and the 6" duct is easier to clean.

I'd say yes, when it deteriorates (which it will), it will not be fun getting it out.

 

[pen]

Galvanized pipe is not meant for exhaust gases of a wood burning appliance. I can't speak to how long it will last, only that if you get that sucker hot the zinc will start to go airborne and you can get very sick from it. If it's only in the chimney, you might not have that to worry about but in general, stove pipe isn't meant to be enclosed in a chimney no matter which type it is. Condensation in there will eat things up fast.

Metal Flu: check it out www.aws.org/technical/facts/FACT-25.pdf

pen

 

[mckishen]

thx for the info everyone. the old galvanized duct is in the chimney only, and with the stove being our primary heat source (on most of the day) there's little chance of any condensation buildup. I've got it tuned in to burn thru the night and I'm having a lot of success with the liner. However, I'm probably going to pull it this weekend while I can still get it out in one piece. does anyone have any suggestions for an alternate liner (ie, stainless, triple wall, etc.). I'm not looking forward to this again as the biggest obstacle was getting the duct to seat all the way into the black elbow at the base of the chimney, so whatever I end up using it's going to have to mate up or I'm going to have to pull the whole shebang and start over before it gets too cold.

 

[mckishen]

Galvanized pipe is not meant for exhaust gases of a wood burning appliance. I can't speak to how long it will last, only that if you get that sucker hot the zinc will start to go airborne and you can get very sick from it. If it's only in the chimney, you might not have that to worry about but in general, stove pipe isn't meant to be enclosed in a chimney no matter which type it is. Condensation in there will eat things up fast.

Metal Flu: check it out www.aws.org/technical/facts/FACT-25.pdf

pen

pen, should I be concerned with the galvanized corrugated sheet metal I've applied to the wall at the rear of the stove? I've got a good size fan aimed at it and it never gets real hot, but it is pretty close to the back of the stove.

 

[pen]

You should be fine. Just watch it. If there are hot spots where the zinc is coming off you'd be able to see it. I doubt you'll have a problem since it is OK to use it for venting other heating appliances, just a quick chimney fire or over fire condition w/ a wood burning appliance is too much for galvanized.

As for finding a SS liner, I bought my liner and connectors for 475 or something like that last year. I figure that's a good investment w/ a lifetime warranty.

How much and what size you need will determine your price of course. Try doing a google search on SS chimney liner or SS wood stove liner and you'll have lots of options to choose from. Call around and talk to tech support to find a company you are comfortable with considering the concerns with your hook-up. The company that has good tech support before the purchase is probably the company I'd personally buy from.

pen