Is it good practice to switch it on only when the engine is idling - the 
compressor and its clutch will then take less of a shock load. Am I perhaps 
a bit obsessive - or does it make sense?

john (john.plant@nowhere.com) gurgled happily, sounding much like they
were saying : 


> Am I perhaps a bit obsessive


Yes.

The compressor cuts in and out all the time in use. It doesn't wait for you 
to be idling to do that.

john  wrote:


> Is it good practice to switch it on only when the engine is idling - the
> compressor and its clutch will then take less of a shock load. Am I perhaps
> a bit obsessive - or does it make sense? 


You mean you actually switch it off?

Mine's running all the time. Even in the depths of winter.
-- 
Steve H 'You're not a real petrolhead unless you've owned an Alfa Romeo'
http://www.italiancar.co.uk - Honda VFR800 - MZ ETZ300 - Alfa 75 TSpark
Alfa 156 2.0 TSpark Lusso - Passat 1.8 Turbo SE -  COSOC KOTL
BoTAFOT #87 - BoTAFOF #18 - MRO # - UKRMSBC #7 - Apostle #2 - YTC #

"john"  wrote in message 
news:NbEte.27865$cN2.17290@newsfe4-gui.ntli.net...

> Is it good practice to switch it on only when the engine is idling - the 
> compressor and its clutch will then take less of a shock load. Am I 
> perhaps a bit obsessive - or does it make sense?


No. As the compressor will cut in and out as required on most modern 
systems, mine therefore spends a lot of its time cutting in with the engine 
at >4000 rpm.