Using aircon with the sunroof open - bad for the a/c?

[g3org3y]

Surely I can't be alone in enjoying having the cold air from the a/c combined with the fresh air from the sunroof?

Is this bad from an a/c point of view. I'll always thought if the a/c is on once should keep all windows (and sunroof) closed.

For some reason in my mind I thought with climate control/aircon, the sensor would detect the temp higher than desired and keep the fan working overtime. With the sunroof open, it's unlikely the temp will ever get to the desired low and as such the a/c would keep working on max.

I'd rather not keep up the practice if it means potentially damaging the a/c.

Would welcome opinions.

[Bluebarge]

Doubt it would damage it but as you are introducing lots of warm air into the cabin via the sunroof it will cause the aircon to work harder, just as your domestic boiler will work harder if you insist on being toasty warm in winter whilst having all the windows open.

[Debaser]

Your air conditioning will be fine. It might not be very effective, but it won't break.

[Dodsy]

Not a problem. I used to have a Saab 9-3 convertible, used to run the aircon on max with the roof down to stop my gentlemens bits from cooking in the sun.

[donaircooleone]

Not really a problem, but it won't really work effectively at all as you are letting heat in and cool air out.

Air only works well in recirculation mode and left to climate control to maintain a temperature, as ultimately you are also cooling down all surfaces in the vehicle.

[Stick Legs]

In some respects this is better, if you don't mind the uneconomical aspect.
One of the swiftest killers of an A/C system is it cutting in and out repeatedly to maintain a temperature.
Keeping it running on a constant load is better.
I run mine in non-recirc mode, always have done and A/C in cars I have had with it has been fine.

On ships we will actually leave a door open if the system starts 'cycling' as it is preferable to waste the cold air than burn out the motors.

[g3org3y]

Thanks for the opinions chaps.

Bluebarge said:

Doubt it would damage it but as you are introducing lots of warm air into the cabin via the sunroof it will cause the aircon to work harder, just as your domestic boiler will work harder if you insist on being toasty warm in winter whilst having all the windows open.

This was my concern.

[kambites]

Certainly wont do wonders for your fuel economy.

[Jezzerh]

We'll hot air rises so I open the sunroof and aim the air con at the floor. I reckon the cool air pushes the hot air out of the roof. I failed A level physics like so could be a load of cobblers!