Just a question about my aircon in my car . . . when I turn the heater control to de-mist the windscreen only, it automatically turns on the air con. Then only sometimes when I turn the control back to heating your feet and the windscreen does the aircon come on. Sometimes it does, sometimes it doesn't. But every time on the windscreen setting.

Would someone please enlighten me??

 

Some answers would be good. Mine does the same, and because I rarely use the aircon the noise the compressor makes sound like an air leak, first time it came on I thought I'd blown my boost hose off.

I'm thinking about stripping it out.

 

Looks like it may be a new age common fault, had 5 classics all with aircon, never had any faults. Hope someone can help you out lads.

 

Aircon will clear the windscreen faster than just blowing air on it, hence it comes on when you switch it to windscreen, every car i have had that had a/c fitted did/does this.

Tony

 

air con helps de mist windsreens faster, something in it that helps, i kno many cars that whenever u go onto widnscreen the aircon comes on and u cant turn it off manually. mis conception with air con its not only used 2 kool the car, but can also b used on hot settings aswell to condition the air and help it demist screens and keep them clearer.

dunno if subaru has a personal settings in ecu, but on vauxhalls u can change certain settings 2 how u want.

 

Aircon dehumidifies air as it is circulated so that's why it automatically comes on when you set the controls to 'demist', the same on every car I have driven with air con or climate control.

As someone has already pointed out, it is meant to be used all year round, not just in summer. This is why so many air con systems fail, lack of use !

 

It all starts to make sense now, thanks guys. A pilot at the work mentioned something similar but he wasn't sure.

So why then would it only sometimes go on when I flick the heater back a notch to warm your feet and the screen too? And other times not?

As a matter of course I run the aircon for about 10 mins per week anyway, just to keep the o-rings etc from drying out.