thomas rubino wrote:No, not a problem at all. Rather handy to have 2" around.
But for a riser she would need a 10" pipe for her 6" riser.
After reading Matt Walkers site, even 1/2" blanket will work, but the 1" works well for pipe sizing.
Mark Brunnr wrote:
Edit: the interface where the burn tunnel bricks and the square opening meet the round riser is a point where the metal pipe could be exposed to high heat, I'd make sure that you use bricks cut and fitted so that no metal is exposed to direct heat. Some will cob a few bricks around the riser to hold it in place with friction, so perhaps a layer of fiber blanket cut to shape that the riser sits on would help too?
Mark Brunnr wrote:You should actually be ok with the wire not melting when used outside the riser buy inside the barrel, as the temperature drops a lot as the gasses hit the barrel top. Many people have used chicken wire to wrap around their insulation and it has worked well.
I plan to make a 6" system with the 5 minute riser design, using a 8" duct. I would give myself an extra inch clearance between the riser and barrel in case any ash accumulates on top of the superwool.
Length: The minimum burn tunnel
length is whatever is necessary to tunnel
under the bell. With a smaller barrel or cus-
tom bell, the burn tunnel could be shorter
without causing problems, but the bell must
never overhang above the feed.
thomas rubino wrote:Yes Jody;Since it is creosote, then something is bad off.
Could be dimensions or as Phil suggested it could be your wood is not dry.
You should be getting hotter on top of the barrel. Because your not, then the temperature in the riser is not getting hot enough to consume the particulates.
That is the only way creosote can get past the riser.
If you can, get us some measurements. All of them. Depth of feed tube , length of burn tunnel roof, height of riser. Size of core (ie) 7.5 x 7.5 or 5.5 x 5.5)
What is your riser made off? Properly insulated ? What is your transition to horizontal area like ?
The 2" riser top gap, should have increased the barrel top temp, So changing it back rite now won't fix your problem. Later changing it to 3" or more is a good idea.