What height of chimney?
Q Will reducing the height of my Morso Squirrel chimney from 23in to 18in affect the draw of the stove much?
HOOPER_TIM, via the CB website
A TONY REPLIES… A lot may depend upon whether the chimney is single- or double-skinned. If it’s double and you fill most of the void between the two skins with expanding foam, the inner chimney will remain hotter and so will draw a little better. It will also depend upon how clean any wind flow is around the chimney. The higher it is above the boat the less turbulence you would get as the wind flows over the boat itself.
My Brunel stove operates perfectly happily with a 12in twinwall chimney, but in blustery weather can puff a little smoke out of the stove vents now and again. If you are cruising then an 18in chimney makes life easier but if you spend long periods tied up, the taller one might draw better.