Air con always on?

[Teutonic_Tamer]

As an aside, whilst I am running my engine in I am avoiding putting the aircon on as I believe it puts a strain (albeit small) on the engine.. am I nuts, or is there any logic in me doing this?

If it is too hot inside your car, then turn on the air con.  Yes, it does use a small amount of engine power (around 3-5 bhp), but on a 200PS motor, it shouldn't be noticeable.  However, if you only had the 75PS 2.0 SDI under you bonnet, you might actually need every one of those apparently lame 75 little ponies for forward motion.

In all seriousnous, your car and engine were designed with the aircon in mind, so even if you leave it on permanently, it shouldn't cause any additional wear on any components.  Indeed, the alternator is more likely to wear the multi-V belt. 

Currently following the progressive max RPM approach that TT advised... only another 100 miles to go and I can move up to max 4500... 

Gold star for my top pupil !!! 

[Teutonic_Tamer]

should run your aircon for at least 10 minutes a week as i believe it helps keep certain parts of the system lubricated and thereofre prevent cracking.  Not sure where i've picked that up so i could be wrong lol

I was told 30 minutes once a month!!

But yes, the general principle is to circulate the PAG lubricant, to prevent the seals in the compressor from drying out, and then ripping when you turn on the air con after its winter hibernation!

A good tip, especially if you suffer with fusty, smelly air con, particularly during high humidity - during the last 5-10 minutes of your journey, turn OFF the air con, and crank up the heater.  This dries the internal evaporator, and prevents water stagnation in the collector drip tray.