I have had a high efficiency furnace for over 20 years, one of the first
ones. It exhausts out the side of my basement wall with a "tee" on the end
of the pipe to split the exhaust up and down. While there is a cloud of
condensation when it is running, it creates no problems, sometimes a small
mound of ice on the ground below. It is in a corner of an "L" and does not
cause icing on the walls around it. Check other installers, that one doesn't
want to install the high-efficiency furnace, probably because he has not
learned how to do it properly, which is bad because they have been around
for 25 years.


"Pep" wrote in message
ups.com...
I have had two contractors in to price out a new high efficiency (90%)
gas furnace for my 25 year old home located in Calgary Alberta. So we
get some pretty cold days

Both have said that a new horizontal exhaust is required out the side
of the house. Both contractors will also drain condensed water from
the furnace to a floor drain inside my basement.

One didn't recommend the high efficiency furnace. He said that the new
exhaust will produce a sizable condensation cloud which will frost over
a window which is about 3-4 feet above the exhaust. As well he thought
condensation would freeze on my neighbors house which is about 6-8 feet
away.


Does a high efficiency gas furnace really produce a cloud of
condensation? (It gets quite cold here, with a lot of freeze thaw
cycles over the winter)

Would the furnace exhaust come out with enough force to frost up my
neighbor's exterior wall 6 feet away?

thanks