Wall thimble for pole barn?

[CJseven]

I’m about ready to start the vent install on a 80,000 big max that will be going horizontal through a wall. Trying to figure out the best way to do a thimble in this type wall, it’s the metal exterior, rolled batting insulation with 2 x 6 wall girts and metal on the interior walls.

 

[Natty Bumppo]

I just vented my 4" pipe for an 80,000 BTU Big Maxx last month. Used a standard thimble but I have flat pine walls inside and out. Are you concerned about getting a good tight seal between the thimble and the corrugated metal walls?

 

[CJseven]

That is one concern for the exterior wall and also the thickness of the thimbles, can they be cut down to fit a thinner wall or build some type of box.

 

[Natty Bumppo]

That is one concern for the exterior wall and also the thickness of the thimbles, can they be cut down to fit a thinner wall or build some type of box.

The thimbles are adjustable for different thicknesses. Both halves kind of slide into each other so you can use them for a variety of wall thicknesses. If you have a thin wall, you could absolutely cut one side down a bit.

Last year I was doing some research here for a different application and I found this member's thread. Might give you some ideas.

https://www.garagejournal.com/forum/showpost.php?p=1336437&postcount=36

 

[CJseven]

Ok thanks I’ll read over that one.

 

[Jagmandave]

Off topic, but why does the poster in that thread need compressed air to run his heater? I understand that it's a used-oil fired heater, but what does it need air pressure for?

 

[nadogail]

Quote from the referenced link. "I still have people donating oil, a neighbor has 15 gallons I have to go and pick up, and a co-worker has a 55 gal drum of oil he says is un-contaminated and I plan to go to his place and pump most of it out into 5 gal containers I have."

The quoted poster is referring to a waste oil burner.

 

[Shop Specialties]

Off topic, but why does the poster in that thread need compressed air to run his heater? I understand that it's a used-oil fired heater, but what does it need air pressure for?

The compressed air atomizes the oil.

 

[Jagmandave]

I see.....I didn't know how that worked exactly.

 

[PBRhunter]

I’m about ready to start the vent install on a 80,000 big max that will be going horizontal through a wall. Trying to figure out the best way to do a thimble in this type wall, it’s the metal exterior, rolled batting insulation with 2 x 6 wall girts and metal on the interior walls.

I know this is old but I’m curious as to what you ended up doing.

 

[CJseven]

Sadly, nothing! the heater was hung and nothing more. It doesn’t get that cold here very often or any length of time. And what little dab of heat I’ve needed over the few years I’ve used a large brick ventless, ran off a portable tank.