"Greg O" wrote in message
...
"Mike O." wrote in message
...

Would it be of any benefit to run a PVC pipe to the inlet of the furnace?
The total length of the run would be about 12 feet, and would involve one
90 degree bend and a 45. The pipe would come out of the house about 30
inches away from the exhaust (is that sufficient?). Also, would I (or
should I) put a final fitting (90 or 45) tilting downward on the end of
the pipe where it sticks outside to keep rain & snow out? The current
exhaust pipe has nothing on the end, it's just the pipe sticking out
about a foot.



There would be some benefit, how much? Don't know, but I would recommend
it too..
Before you attempt this I would get a manual for the furnace. I work for a
Ruud dealer, which is the same furnace, different label. The air inlet
requires a condensate catch "T" to keep moisture in the fresh air from
making it's way to the furnace. Also the air inlet is supposed to be close
to the exhaust, within a few inches, generally slightly below, with an
elbow pointed down. All this info will be in the manual. find one, read
it, and follow the directions to the letter! It may look easy, and it
really is, as long as the instructions are followed. I have be out on
calls to solve problems with furnaces that are not running properly. Often
it is just a problem with the install. Too much pipe, too many elbows,
wrong diameter of pipe, and so on.

What size of furnace is it? Larger furnace require larger pipe. Longer
runs require larger pipe. It may be possible that your furnace is not
installed properly right now!
I can e-mail you a manual if you give me the model of the furnace.
E-mail me if you like.
Greg
Thanks for the response. I've replied via email with more info, but in case
you don't receive it, the furnace is a Rheem "90 Plus" upflow natural gas
furnace. I think it's in the85K to 90K BTU range.

The previous owners didn't leave any documentation. I've done some
searching, and have found a spec sheet and a "use and care guide", but
haven't located anything relating to the inlet air piping, so if you can
point me to site with more info, I would appreciate it.

Mike O'Donnell