Vent stack extension, what the heck!

hotrod53 · Mon Jul 09, 2007 8:18 pm

I purchased a 16" extension for my vent stack, the instructions state remove the 3 screws-pull up the cap-install the extension-put in the screws. This all sounds great with one exception.......I can't find any screws! Is it possible that he screws are below the square piece mounted to the roof? I felt all around it thinking that the screws are in the roof coating but didn't find any. Is it possible that there are no screws and they are rivets? Rivets could easily hide in the old coating.

I have a Miller furnace with an 8" outside pipe and about a 5" inside pipe, it draws combustion air between the two pipes.

We quite often have to shovel the roof before lighting the furnace, this should fix that. Propane flame outs SUCK!

Yanita · Mon Jul 09, 2007 8:57 pm

Hi Hotrod,

I am not a HVAC tech so I am going to move this thread to that forum, please follow it over there,.

Would like to say thanks so very much for making individual post for your questions, makes them much easier to answer and no confusion!

Again thanks and welcome...

Yanita

hvac1000 · Mon Jul 09, 2007 11:46 pm

Usually all you have to do is get the top cap off and then add the extension. When done put the top back on. The cap could be a little rusty and you may have to move it around a bit to get it off. Most times there are screws of some type there so the top does not come off in high winds etc.

hotrod53 · Wed Jul 11, 2007 3:35 pm

hvac1000, the problem is that I don't see or feel any screws, have you seen any that were riveted? There is a little roof coating around the stack but I don't think enough to conceal a screw head. It could however conceal a rivit head...

Does the top of the head typically come apart in such a way that I could remove it an l ook down the stack to see where the screws are?

hvac1000 · Wed Jul 11, 2007 6:23 pm

Usually on the ones I have worked on there was always a screw from the cap to the pipe. Now I guess someone could have used something else to make sure the cap stayed on. The top usually comes off and then you can see down the inner part of the flue. It is a pipe in a pipe system.

Robert · Wed Jul 11, 2007 8:11 pm

Hi,

Just as a side note, some of those older roof-jacks did not have removeable caps.

For those, you would go from below and use an "interior" extension.

You add the extension into the piping.

If this does not work, you can always replace the roof-jack with a new one that has removeable cap.

Take care and best wishes,
Robert

hotrod53 · Sun Jul 15, 2007 10:27 am

My home is an '89 Champion, I guess that qualifies it as an "older" home. I did not look inside to see if there were screws in there. If I needed an "inside extension", I assume that means that the piece that I purchased would not work??

HVAC1000's description makes me wonder.... when you say remove the cap you are referring to screws in the side of the pipe and not screws in the top...correct? There are screws in the top of the upside down looking pan and screws on the top of what looks like a flat steel plate, just none in the side of the pipe.

If I were to replace the roof jack, you are referring to the wedge shaped piece that is mounted to the roof...right? To do that I would rip the roof coating off and it is zip screwed into the roof I would assume?

Pardon the newbie questions....I'm capable yet inexperienced in the world of mobile homes. That's the beauty of forums like this, guys like me can learn from guys like you! Give me a small block Chevy and I'm right at home, I'm familiar with the working of that...LOL!

Robert · Wed Jul 18, 2007 7:56 pm

Hi,

The roofjack is the whole thing, from furnace to flue cap.

Go here to see all the different roof-jacks and extensions, etc... :

http://www.mobilehomerepair.com/ColemanChimneys.html

Take care and best wishes,
Robert