I have the same problem. One room is 2 degrees hotter or colder than the
rest of the house.
I got a quote for $ 550 to run 30 feet of larger ducts from the furnace.
Don't know about a duct fan. Could imagine that it is somewhat noisy right
in the duct. Of course, you would have to run a 120 Volt Cable from the
furnace blower to the fan, wired in parallel, unless you want the fan on all
the time.

I am lazy and decided to live with it. My parents had to contend with more
than 2 degrees temp differential. The Cro Magnon Men had even bigger
problems (drafty caves).
--
Walter
www.rationality.net
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"Christopher Nelson" wrote in message
...
I have a room that never seems to get enough heat or AC. I have a
split level. The furnace is below the family room and the cold/hot
room is above the family room. You'd think that'd be a short-ish run
of duct work but it does bend a couple of times. I'm thinking of
putting a booster fan like
http://www.comfortgurus.com/product_...roducts_id/563
in. Do they work? Any comments on the brand or model I should be
aware of? I'd rather walk into my h/w store or home center and go
home with one but I can't find one locally. Is that to be expected or
have I just looked in the wrong places?