At 02:08 PM 12/5/2011, Alistair Bell wrote:
>Funny how the owner's manual says the vent should be uncovered
>except during car washes.

Well a) it makes it *really* hard to light.**  And b) the covers
deteriorate in the sun.  I can't see any other actual problem with
leaving them on, and it keeps wasps etc from building nests in the flues.

**I once had a house trailer.  It had a little six-inch-high mushroom
thing called a roof jack instead of a proper chimney for the
furnace.  I went away for a week, there was a big snow, I came back
and it was ten below (Fahrenheit) inside the trailer.  The spider
plant didn't like it but surprisingly the plumbing survived.  Anyway
I was pretty slow - I had the propane furnace puff back in my face
three or four times before I thought to go clear out the roof jack.

Yours,
David