Re: A/C recirculation/warm air from dash ponderings..

[johnc@together.net]

Robt-

> Depends. I *DO* want recirc when it's 99.9% RH outside. By default,
> "A/C" selects recirc on some models (on '83 UrQ, it's forced, you
> have no option; on '98 A4 it's selectable, forced on "max"). recirc
> will dry the inside faster than non-recirc, almost always. But it's

i must respectfully totally disagree.  maybe i don't if 'always' is dependent on 99%
RH.  IME any other time recirc is typically the 'fog windshield' button.

> Obvious solution -- put the evaporator downstream from the heater core,
> then when it's cold, you're blowing heated air over the evaporator, so
> it won't ice up, just pull the moisture out of the air. Then you can
> use the "A/C" to dry out the car even at 10F.

except (my usual caveat: i don't know what i'm talking about) don't you have to cool
the air below it's dew point to condense the water vapor?  and that dew point won't be
changed by going through the heater, so you heat it up, only to cool it down again, and
then you get nice frosty air in the cabin, right?

> The A4 is (according to my salesdroid) equipped with a variableschmariable
> compressor which is always on, but load-varying, or some such thing.

yeah, i know a guy with an A4 Avant who claims 'they fixed it, there's no power loss'.
get this - he actually believes what the sales guy tells him.  i think (as you are
alluding) it's salesdroid doublespeak-regurgitation of propaganda.

when i hit the snowflake, the car bogs down.  maybe the load varies as it runs, but
every clutched AC does the same thing really.
--

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John J Cunningham III           Project Leader / Technical Analyst
                                             Country Home Products
johnc@together.net                            (802) 877-1201 X1242
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