Out with One, Up with the Other

Out with One…

I moved the boiler vent from the existing furnace and gas water heater chimney to the utility room wall, so the next step was to take out the old chimney. I also put a 3″ PVC pipe through the wall on the other side of the utility room to route outside air to the stove.

New external air vent

New external air vent and old chimney.

I removed the pipe that extended into the house–by unscrewing the seams on the outside.

Hole from removing  chimney pipe

Hole from removing chimney pipe

Then I reinstalled the cap with a couple of screws so it would not blow off.

Shorter chimney cap

Shorter chimney cap for unused chimney. Air intake vent is on the left.

To cover the hole, I cut a piece of plywood and installed it to prepare it for insulation and the thermal envelope sealing. The plywood was caulked and glued in with liquid nails and then the special air barrier tape was applied.

Plywood patch cut and sealed

Plywood patch cut and sealed

Up with the Other…

New Chimney

New Chimney

I also ordered double wall chimney from Menards (Selkirk brand)–as that was the least expensive source I found. I made a couple of errors as usual though. I did not understand that there was a difference between a pipe increaser and a pipe reducer. In face, I did not realize there was such a pipe as an increaser. The difference is in the circumference that the pipe needs to fit together. I jammed the reducer into the upper pipe through sheer force of will and the use of tin snips to open part of the interior double wall to accept the lower pipe. It worked well enough although there will be some rough spots that will catch soot. Not enough to overheat it at the seam I hope.

I also had to take the extension off the 18″ extension pipe that I had ordered since the pipes joined better at the required 45 degree angle from the stove without the extra length. A third piece I found I didn’t need was the stove adapter—the double wall pipe fit on just fine without using that piece. So roughly $50 more pipe than I needed and one wrong $55 dollar pipe that I did not replace. (yet)

The chimney requirements are translated from Polish and the language for the stove directions is a bit hard to interpret but not impossible.

Directions from the manual:

At connecting fireplace flue – should turn attention on following recommendations:

To provide the correct work of device the chimney draught should figure out about 15 Pa. The flue should be performed from heat-resistant steel and leaded straight as possible and with the smallest number of deflecting.

    • Connecting flue with chimney should be made at an angle of 45o. (Why 45 degrees? I’m not sure–to extend the length of the pipe to improve the draft?)
    • The assembly of simple section after exit from flue connection courts about length min. 30 cm directly. (about 12″ of flue from the top of the stove)
    • The connections of flue should be tight.
    • Fireplace should be connected to individual flue.
    • External chimneys should be insulated.
    • Room in which fireplace will be installed should be equipped in ventilations.
    • The minimum intersection of chimney is 400 cm2 and height this 6-8 m. (78 square inches and 19-26 ft. tall–taller than our install so hope we have enough draft. We have about 7 ft. inside, 2 ft. in the roof, and 4 ft. outside–or 13 ft–6 ft. too short but I’m not going to worry about it. I’ll bet the stove will draw just fine on cold enough days.)
    • Air to fireplace should be brought by channel about intersection=100mm (4″ intake air vent–and I’m using 3″ PVC through the wall but increasing that to 4″ inside–close enough I hope.)


Chimney with 45º angle

Chimney with 45º angle

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