My air conditioning has usually been on AUTO since I got the car from new about 80,000 miles ago. Never been stunningly cold but has worked well enough for me at 40C ambient. I accept that some refrigerant  will now have been lost so have booked in for a full service at an aircon specialist. I will be interested to find out how much of the toxic stuff has been lost. I will not be hopping up and down if frost and icy blasts do not appear at the vents.

 

BTW my wife's Getz is 7 years old, 27,000 miles, the manual air conditioning is used but intermittently and still produces very icy air.

Edited 24 May, 201511 yr by gregoir

Your fuel consumption must take a hit having it on auto all the time. 

Every car I've had with AC or climate has it switched on or at auto. My skoda doesn't have climate but the AC stays on all the time - I've never noticed any significant difference in fuel consumption on any car.

I've tried observing the mpg on the trip computer experimentally with the air con off and on. On the flat I could not see any consistent difference attributable to the aircon button.. I think the AUTO limits the usage of the aircon and thus the energy consumption.

This debate has been around the block a few times. I recall no-one with AUTO climate control was unhappy with mpg.

mine adds about 1L/100km with AC on.

 

What refrigerant do they use in the UK? R134A?

Air conditioning has just been checked serviced, for the first time, at a local specialist for £49.95. I watched the whole process. 335g out of 525g of refrigerant remained after 6 years and 80000 miles.

The temperature at a dashboard vent was tested. Before 6.5C and after servicing 4.9C running flat out in the manual mode. I normally run in AUTO so I don't demand chilled air just the usual 21C or so. 

I was told that aircon temperatures can vary between 0.5C (a recent Ford after a service) and 7C (an Astra ditto) in their experience.