Re: 90Q20V CLIMATE CNTRL. DRAG

["Graydon D. Stuckey" <graydon@apollo.gmi.edu>]

On Mon, 30 Sep 1996, Dan Masi wrote:

> I assume that this would be the case in any moderately sophisticated
> climate control (e.g. Audi's); I hope that when I switch on the
> AC and drive for a few hours, that the compressor is not engaged
> the entire time!
> 
> Dan Masi
> '96 A4Q
Dan,

	You are correct.  The compressor should cycle on and off under 
normal operation.  This has been a source of many complaints n the 
industry.  There has been alot of work put into reducing that shock to 
the drivetrain when the compressor cycles on.  Clutch squeal has been 
quite a problem also.  Normally, there is a pressure switch on the high 
side of the compressor, and as soon as the pressure reaches a cut off 
point, the clutch is disengaged.  Then, when the pressure drops below a 
certain point, the clutch is engaged again.  This cycle is usually around 
once every 10 seconds.  Sometimes longer, sometimes shorter.

Later, ---------------------------------------------------------- 
Graydon D. Stuckey 	'85 Mazda RX7 GS, no toys 
graydon@apollo.gmi.edu 	'86 Audi 5000 CS Turbo Quattro, has toys
Flint, Michigan USA	'89 Thunderbird SC, lotsa toys