On Nov 4, 9:47*am, DerbyDad03 wrote:
On Nov 4, 8:58*am, lj wrote:





On Nov 4, 8:28*am, Art Todesco wrote:

On 11/3/2010 11:45 PM, DerbyDad03 wrote:

On Nov 3, 10:14 pm, Steve *wrote:
On 11/3/2010 1:21 PM, DerbyDad03 wrote:

I have a Goodman 90+ furnace with a 3" PVC output pipe, which ends in
vertical T.

Here's a side view, with W being the wall:

W
W * * * |
W-------|
W * * * |
W

I've always thought that it makes more noise than it should when the
furnace is on. It's sounds like a steam pipe at a factory.

If I were to compare it to anything, I'd say it is 3 - 4 times louder
than my AC compressor.

Is that normal?

Goodman eh? *LOL. *They do make some noise. *I'd say mine is 50 times
louder than my a/c unit. *My a/c unit is very very quiet. *I'd say
standing right next to the exhaust/intake is about the same as say a
household vacuum at 50 feet.

--
Steve Barker
remove the "not" from my address to email

OK....then I'm not worried...just not happy.

Thanks!

I don't think my Goodman is anywhere near as loud as a vacuum, nor
is it as loud as the AC/heat pump. *The AC/heat pump (Amana) isn't
that noisy, but the frequency of the noise is different. *The
exhaust/intake of the furnace has more high frequency components.
All that said, I have an air induced water heater with an exhaust
about 10' from the furnace intake/exhaust and it is by far more
noisy than the furnace or AC/heat pump and it runs in the summer
when you are outside. *Not only is it noisy outside, it is real
noisy in the basement. *I hate it. *But, the central vac outside
vent beats them all. *I probably should put a muffler on it.- Hide quoted text -

- Show quoted text -

Interesting. *Does it seem the noise is the vent fan? *Or turbulence
noise in the pipe? *You possibly could use a larger pipe to reduce the
air speed. *High eff furnaces condense at the unit so slowing the vent
gas speed should not matter. *If it's fan noise then you'd have to
play around with the fan it's self to reduce the noise.- Hide quoted text -

- Show quoted text -

Sounds more like turbulence. I don't hear any of the same noise inside
the house, so I doubt it's the fan.- Hide quoted text -

- Show quoted text -

Well it would be a bit of an experiment and depend on how complicated
your pipe run is. Increasing from 3" to 4" almost doubles the area.
From 7 sq in to 12.5 sq in. 6" pipe (I'm pretty sure there is not
any 5") is 4 times the area of the 3". But pvc pipe is not real cheap
in these sizes so if you have a straight run that is easily accessed
it might be worth the experiment but otherwise I don't know. And keep
in mind it is an experiment.