oil furnace chimney

[malarson]

I'm in the process of installing a used Lennox fuel oil furnace in my garage. I'm not sure about the chimney, I know it needs to be a class A, but holy cow is that expensive! I am running it throught the back wall (2x4 stud), can I just run the class A throught the wall and use the cheapo stuff to connect to the furnace and also outside for the chimney stack? This furnace came out of my dads house, he has the galvanized single wall connecting the furnace to his brick chimney. thanks.

 

[MyDomain]

26 guage is okay till you get to the wall as long as you have good clearance to combustibles (18+ inches). Then what, are you going into a chimney crock or are you running it up the wall?

Here is a reference .

 

[malarson]

Thanks for the reply. After going through the wall (to the outside) it will run up past the roof. I have a 1 ft overhang so I will keep it at least that far from the building.

 

[MyDomain]

You'll need to use Class A then up the wall. I would regardless in case something got against that 300 degree pipe. Plus you would be required to outside anyway due to condensation issues.