Hart and Cooley elbow kits can't be used outside?

[Badfish740]

I just got my permit approved for the installation of my 28-3500 add-on furnace plus the chimney. I was going to use an offset to route the chimney around a 1st floor window (the furnace will be in the basement), but I'm now seeing in the Hart and Cooley installation guide that elbows may not be used outdoors. Anyone know why? What do I do now?

 

[BrotherBart]

Looking at their catalog if you wanted to use 45 degree elbows you couldn't anyway because they are only for gas oil or gas chimneys, not wood.

 

[MountainStoveGuy]

they also have 45*s for class A, but only listed for canada. 30*s and 15* should be ok. Can you cut and paste the text that you are reading?

 

[Badfish740]

From the installation manual which can be found here.

Insulated 15°, 30° and 45° Elbow Kits
• The insulated elbow is used when offset is required.
• Locking bands must be used on all elbows.
• A maximum of 6 feet is allowable between offsets.
• Elbow is fully insulated and can be used with the same 2-inch clearance as chimney lengths.
• Elbow support must be used with all offset installations and will support 15 feet of chimney.
• Elbows do not have twist-locking ridges, so they can be rotated to attain optimum positioning offset and allow
chimney to return to correct vertical alignment prior to installing locking bands.
• May not be used outdoors.
• 10", 12" and 14" sizes available in 15° and 30° elbow kits only.
• 45° elbows may be used only with oil or gas appliances.
• Elbow kits include: 2 elbows (Exception: 12" and 14" sizes include four 15° elbows assembled into two 30° elbows), 4 locking bands (Exception: 10", 12" and 14" sizes include two locking bands), 1 elbow support, All hardware

Just out of curiosity I checked the Supervent manual online to see what it said and there again: NEVER use an offset outdoors.

I was going to use two 15 degree elbows with an 18" section of chimney in between, but as far as I can tell even that isn't recommended under any circumstances. I had thought that using an offset to go around a window, etc...was commonplace, but I guess not, now I'm just curious as to why. It looks as though I'm just going to have to go straight up and block a small portion of the window.

 

[MountainStoveGuy]

that is interesting. News to me. I tell ya, you learn something new everyday here. I will check my excel manuals as well. Im guessing there saying that because you cant use elbow straps? but wall supports below and above the elbow section should give enough support. Summit? Dak? JTP? any clues here?

 

[MountainStoveGuy]

ya think pook? 15* is a long way from horizontal.

 

[MountainStoveGuy]

The Xcel chimney does not have any such wording i can find.

 

[jtp10181]

Never heard of such a thing. Cannot find anything about it in the duravent manual.

http://duravent.com/docs/instruct/L150_July09.pdf

 

[MountainStoveGuy]

The Xcel chimney does not have any such wording i can find.

that seems to reference an interior install

correct. they dont reference the outside wall
http://www.icc-rsf.com/c/icc/file_db/maindocs_e/EXCELUSA.pdf

the OP should call cooley and ask then whats up!

 

[Badfish740]

Got my answer from Hart and Cooley. Because the elbows are made with a swivel for easy positioning they are not water tight and therefore cannot be used outside. I suppose that if other manufacturers make rigid elbows that they would be ok to use?

 

[MountainStoveGuy]

most of the elbows do not swivel. Simpson elbows and excel elbows do not swivel.

 

[theheatelement]

It is most likely because the outside of them is not made of 304 stainless steel but more likely 409 or a galvanized finish.