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Hi,

Is it OK to keep the AC always ON even before switching the car off. should I follow the sequence of switching the car on first then after a minute switch the AC on and switch the AC OFF then switch the car OFF. Does it affect the AC compressor badly if keeps the AC always ON.

In my previuos cars, I used to follow the sequence. But, I don't know about my Volvo.



:confused:
 

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It should make no difference at all. I always leave my A/C on when shutting the car off.
 

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This was more of an issue with older cars. If you listen next time you start the car, the system waits a few seconds before switching on the A/C compressor even in auto mode. I keep A/C on most of the time, but heard some people switch off the A/C early to reduce condensation and possible mold growth after shutting off the car.
 

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...but heard some people switch off the A/C early to reduce condensation and possible mold growth after shutting off the car.
This is what I do and have never had an issue with moldy A/C. I actually leave my A/C compressor off all the time except for when I need cooling. Perhaps that's why my A/C compressor is still quiet :thumbup:
 

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I usually let the computer worry about it. If the weather is nice I'll turn off the AC to just get fresh air.
 

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I usually turn the A/C off before I turn the car off. Supposedly it makes the compressor last longer, I dunno but it's just a habit of me.
 

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It should make no difference at all. I always leave my A/C on when shutting the car off.
it hasnt hurt any of my previous cars & trucks no issues in almost 7yrs & the a/c in my cobra is still awesome !!

This was more of an issue with older cars. If you listen next time you start the car, the system waits a few seconds before switching on the A/C compressor even in auto mode. I keep A/C on most of the time, but heard some people switch off the A/C early to reduce condensation and possible mold growth after shutting off the car.
this !

I leave it in auto mode all the time.
same here 90% of the time unless it gets to cold or hot
 

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From what I've been told on these and other forums, for many years Volvo had fans built into the vehicle which continued to blow as needed (even when the vehicle was off) to clear condensation in the air conditioning system. Is this no longer the way it is done? I had just assumed that the newer fans were silent since I don't hear my new XC doing it as often as the old XC did.
 

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Obviously...the A/C compressors is powered via a rely...so it make absolutely no difference either way...modern rotary A/C compressors are very durable! They're designed to be left in the auto mode.
 

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I had always turned the AC off for a few minutes before parking the car but I think that is no longer necessary. A call asked that very question on Click and Clack a few months ago and got the same answer.
 

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Switching AC on

If really care about your car health. You should follow these rules, Always switching the car on first then after a minute switch the AC on. I am a Car AC repair expert from Dubai Alqusais Car Garage.
 

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If really care about your car health. You should follow these rules, Always switching the car on first then after a minute switch the AC on. I am a Car AC repair expert from Dubai Alqusais Car Garage.
I'd be surprised if the AC compressor's clutch would engage on startup. Usually they're disconnected when starting the car so the extra load doesn't make it hard to start. Knowing that, I would say it doesn't matter if the AC is on when you start the car.
 

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If really care about your car health. You should follow these rules, Always switching the car on first then after a minute switch the AC on. I am a Car AC repair expert from Dubai Alqusais Car Garage.
You may be an "expert" but you're also absolutely full of it.

There is no need whatsoever to turn off the A/C before starting the car. Modern cars automatically disable accessory power (including the A/C compressor clutch) while cranking the engine. And by "modern" I mean any car built in probably the last 4 decades - my 1986 Porsche 951 cuts out electrical accessories while cranking.

I've never turned off the A/C in my 1998 Volvo S70 in the entire time I've owned it and with 200,000 miles on it, the A/C has never had a single problem. It still has the original factory charge in it.
 

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You people that say you always leave your car in Auto or never turn off your A/C... do you leave it on in the winter when you're heat the car up too?
 

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You people that say you always leave your car in Auto or never turn off your A/C... do you leave it on in the winter when you're heat the car up too?
Yes. Using the A/C in the winter is a requirement here in the Pacific Northwest because otherwise the interior of the car will fog up heavily. Running the A/C dehumidifies the air inside the car and prevents the windows from fogging up, even when the air coming out of the vents is hot. This is why every car for probably the past 30 years forces the A/C on when you select the "defrost" setting for the heater vents.

Basically, the best thing to do is have the A/C "on" and set the controls to automatic. Let the system do its thing and use the A/C whenever it thinks it needs to.
 

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Yes. Using the A/C in the winter is a requirement here in the Pacific Northwest because otherwise the interior of the car will fog up heavily. Running the A/C dehumidifies the air inside the car and prevents the windows from fogging up, even when the air coming out of the vents is hot. This is why every car for probably the past 30 years forces the A/C on when you select the "defrost" setting for the heater vents.

Basically, the best thing to do is have the A/C "on" and set the controls to automatic. Let the system do its thing and use the A/C whenever it thinks it needs to.
Agreed, also in PNW and I found that during the winter if I have the wife and kids in the car with me especially if we've been outside in the cold even just putting the car into ECO mode (I think it still uses the AC compressor but in reduced capacity) will cause the windows to slowly fog up so it has to be in full AC mode. If I'm by myself I don't notice it.
 

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From what I've been told on these and other forums, for many years Volvo had fans built into the vehicle which continued to blow as needed (even when the vehicle was off) to clear condensation in the air conditioning system. Is this no longer the way it is done? I had just assumed that the newer fans were silent since I don't hear my new XC doing it as often as the old XC did.
ive never heard of any car that leaves an interior blower fan on after switching the car off. My 2012 s60 certainly doesn't do that.
 

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ive never heard of any car that leaves an interior blower fan on after switching the car off. My 2012 s60 certainly doesn't do that.
It doesn't leave the fan on. It waits until the car has been sitting for 30-45 minutes, then runs the fan for a few minutes to dry out the evaporator housing. It's been a standard feature of Volvos since the P2 chassis cars.

By waiting, it allows the evaporator to warm up and stop gathering new condensation before it attempts to dry it off. Most people won't ever notice it. You can find the settings for it in the CCM module when you do a VIDA scan, but your 2012 S60 absolutely has it - they all do.

I should add that this does not run every single time. There are various criteria that need to be met. For example, the exterior temperature must be above a certain point (IIRC it was above 75 Fahrenheit for the later P2 cars with the early cars needing a temp around 82 F), the battery must be in good condition, it's only done once per every so many hours of operation regardless of other conditions, isn't run unless the A/C compressor has run continuously for a certain amount of time during a fixed interval prior to switching the car off, etc. Basically Volvo uses a fairly complex algorithm to determine when it happens in order to avoid running it too much and draining the battery.
 
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