proper way to run pellet pipe through cinder block to flue...

[vtdave]

I am installing a Harman PF100 in my basement. The exhaust piping is 4" ICC double thickness pellet pipe. My goal is to vent it to my chimney flue. There is an existing 5" circular access cut through 16" of cinderblock to the flue (from an oil hot water heater that used to be there).

Question: what's the best way to get my 4" pipe into that 5" hole? Also, how far into the cinder block should I run the pellet pipe? Should the pipe end with an upward facing elbow into the chimney or does it not matter? On the flipside, could I run the pipe, say, 6" into the cinder block and call it good as long as the pipe-to-cinderblock interface is airtight? I'd like to leave the flue unobstructed so I can sweep it easily from the cleanout at the bottom.

Thanks very much, guys.

Dave

 

[rona]

People say you should run a flex liner up the chimney otherwise the chimney will be to cold to draw properly. I think it depends on a couple things.
If you have a good clay liner I would try it and see if it works without the expensive metal liner. I know of three people besides myself that do what you are planning and we have had no problems. But it gets pretty cold here and with the stove running 24-7 for 3 weeks straight between cleanings none of us has had any problems.
Regarding your furnace 5 inch vent and your 4 inch pellet furnace vent you can buy a adapter or buy a 5 inch "cap" and cut a hole big enough to run your pellet stove pipe through it.
I would also just run a pipe straight into the clay liner with-out a angle on the end. Reason for that is the soot will settle in that elbow and pretty soon you will have blocked pipe.
You have a clean out on the bottom of the chimney which is great. Just clean it once a year and you will be fine.
I could send you a picture of what I did as it seems similar to what you are going to do. just send me a e-mail.

 

[vtdave]

Thanks very much, Rona. My clay liner seems in good shape, so I'll try that for starters as you suggested

 

[dac122]

You can definitely buy a 4 to 5 adapter.

If I understand right you're thinking of using the cinder block as part of the flue does not sound so great. I would have a pipe to pipe interface all the way. Hope I understood you.

Don't know if you've used the ICC pipe before but you're gonna love it. With regards to sweeping, that pipe will come apart at any joint very easily. Heck you don't really need any screws since the seal is so tight. I guess I would go as far as you can with the ICC since it does come apart easily. There are lots of pipe brushes and techniques to get it clean. There is also no law against using multiple clean-out tees if you like, but somewhat pointless and expensive since the pipe comes apart easily.

 

[vtdave]

You can definitely buy a 4 to 5 adapter.

If I understand right you're thinking of using the cinder block as part of the flue does not sound so great. I would have a pipe to pipe interface all the way. Hope I understood you.

Don't know if you've used the ICC pipe before but you're gonna love it. With regards to sweeping, that pipe will come apart at any joint very easily. Heck you don't really need any screws since the seal is so tight. I guess I would go as far as you can with the ICC since it does come apart easily. There are lots of pipe brushes and techniques to get it clean. There is also no law against using multiple clean-out tees if you like, but somewhat pointless and expensive since the pipe comes apart easily.

Thanks. Any advice on whether to use silicone with ICC pipe - say where it meets the furnace or at the joints between pipes? You make it sound like the ICC is pretty tight, which makes me question the need for silicone. I ask because cleaning and disassembly would be so easy w/o silicone...

 

[dac122]

Only places you need silicone: at the appliance adapter on the stove, and at your 5 to 4 reducer and 4 adapter.


Silicone and screw your reducer, cut a hole in your adapter to accommodate the 4" pipe, silicon and screw on the adapter, insert and silicone your pellet pipe, and off you go.

Here are some pics to show you how it should work. This is a 7" wood stove pipe to 6" reducer, then an adapter, with a 3" 45-elbow inserted. Everything else has no silicone!

Click on the pics for a close up.

Reason ICC works so well is it has those big orange replaceable seals. No silicone needed unless you want to torture yourself.

 

[vtdave]

That's very helpful. Thank you. And a nice, clean installation as well!

 

[dac122]

Thanks. Post some pics when you are done.

We love seeing successful installs!