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On May 13, 12:49 am, "-->> T.G. Lambach <<--" <"T.G. Lambach at
NoHamorSpamcomcast.net"> wrote:
> The foam tube is the aspirator tube for the climate control - it draws
> cabin air over the inside temperature sensor and exhausts same into the
> blower intake. A piece of 5/8" drip irrigation tubing will serve as well
> (but not as quietly).
For a quieter version, use a piece of foam home hot water pipe
insulation that is sold at Home Depot or similar stores and made to go
around home copper water lines. Don't remember the exact size I used,
1/2-3/4, but it fits perfectly.
A while back, after having the AC worked on in my 300SD at a local
shop, I had noticed that the blower seemed to be making more noise at
the higher speed. Finally traced it to a vacuum hose like sucking
sound coming from the small air intake for the sensor in the center of
the dash. Then for a couple years I just put up with it, because for
the life of me, I couldn't figure out how this could be or what was
causing it, so I thought I must be imagining that it changed. Then,
one day while doing some work, I stumbled upon a piece of auto heater
hose that the shop had used to replace the foam piece of pipe. I
replaced it with the above solution and it made a substantial
difference in deadening the sucking sound. A hard rubber hose
transmits noise, while a foam type deadens it.
I think it's still not quite as quiet as original, but close. I
thought about gluing a piece of soft cloth to the inside of the
insulation pipe, which I think may cut it even more. Would be easy
to do, as the insulation is usually sold split when you buy it, with
an adhesive already on the joint, covered by a pull strip that you
remove to seal it.
Tom Plunket - 20 May 2007 05:22 GMT
trader4 wrote:
> > The foam tube is the aspirator tube for the climate control - it draws
> > cabin air over the inside temperature sensor and exhausts same into the
[quoted text clipped - 5 lines]
> around home copper water lines. Don't remember the exact size I used,
> 1/2-3/4, but it fits perfectly.
Ok, I wondered if this was state of the art for this sort of repair. :)
I thought I might look for something softer, more like the original
hose, but figured pipe insulation would work in a pinch.
thanks,
-tom!
--
trader4@optonline.net - 20 May 2007 16:11 GMT
> trader4 wrote:
> > > The foam tube is the aspirator tube for the climate control - it draws
[quoted text clipped - 16 lines]
>
> --
If you find something better, please let us know. I'd say the pipe
insulation may be about 75% as effective in deadening the sucking
sound as the original, but since I don;t have an original to compare
it too, no way to tell for sure. If you want to test how much
noise is still coming from the temp sensor intake, just block it with
your fingers. With a piece of plain rubber hose, most of the
objectionable AC noise is coming from that little sensor opening.