Damper or insulation on your OAK pipe?

[hearthstoneheat]

I was wondering if you guys have a damper or insulation on the OAK pipe to your stove? The installer didn't put a damper on mine and I don't have insulation around it. I noticed the pipe got cold enough to condense water on it. Can someone show me their set up and/or tell me where to get a damper? Thanks.

 

[Backwoods Savage]

I've not heard of a damper used there but I suppose it could, but I don't know why. When we've had a OAK we never noticed any condensation so that is new to me.

 

[LLigetfa]

I have both. It should have insulation or else you may have moisture problems from condensation. In my former home, the OAK was about 10 feet long and ran down through the floor and through the crawlspace. I had insulated the first 8 feet of round pipe in the crawlspace but I transitioned it to a 2 foot length of 3x10 duct to come up through the floor between studs, and into the stove. The 3x10 duct section would sweat or frost up and drip down into the crawlspace.

What you call a damper, I call a positive shutoff. If/when it was very cold out and I didn't have a fire going, there would be frost on the glass and metal from the constant draw of the flue.

 

[hearthstoneheat]

I have both. It should have insulation or else you may have moisture problems from condensation. In my former home, the OAK was about 10 feet long and ran down through the floor and through the crawlspace. I had insulated the first 8 feet of round pipe in the crawlspace but I transitioned it to a 2 foot length of 3x10 duct to come up through the floor between studs, and into the stove. The 3x10 duct section would sweat or frost up and drip down into the crawlspace.

What you call a damper, I call a positive shutoff. If/when it was very cold out and I didn't have a fire going, there would be frost on the glass and metal from the constant draw of the flue.

Is the positive shutoff something you made yourself? What kind of insulation did you use?

 

[LLigetfa]

The insulation is fibreglass in a plastic sock that slips over the pipe. Where it gets close to the stove, I transitioned to foil backed insulation and used foil duct tape. This was to insure that if the draft ever reversed and hot flue gasses entered the OAK, there would be no risk of fire.

The positive shutoff for my stove was available as a factory option but would have required that I go outside to open and close it. I rigged up my own with a choke cable instead so I can open/close it at the hearth. If I had thought of doing it before I had all the drywall up, I might have done it different but this was the easiest way to retrofit one.

 

[hearthstoneheat]

Nice set up thanks for sharing. That may be something I could rig up.

 

[begreen]

Great idea, that really is a choke for the fire.

 

[Highbeam]

I also have a Hearthstone and appreciate the 100% sealed intake air path to this stove. All combustion air enters through a 3" nipple on the rear. If I were to install a shutoff I would put it right there at the stove using some sort of a butterfly in the nipple. This would be useful for preventing runaway fires, snuffing a chimney fire, extending burn times, and possibly shutoff when the fire is out in the winter but I usually burn in the winter so no big benefit there.

I use the OAK to draw combustion air from my ventilated crawlspace, we don't have many basements or slab-on-grade homes here in the northwest. The crawlspace air is cold for sure but not so cold as to create a problem with frost. The only place that you should have an issue with moisture accumulating on the OAK tubing is within the living space of your home. I would not insulate the tube, it is big and ugly enough already. Check out my OAK photos in my sig.

 

[Renovation]

All combustion air enters through a 3" nipple on the rear. If I were to install a shutoff I would put it right there at the stove using some sort of a butterfly in the nipple.

Thanks for the great ideas, folks. Thanks to you, I'll include an OA shutoff on my install.