Q about A/C ?

[lentiformnucleus]

hey guys i know this is probably a stupid question but does turning the car off with the A/C on damage it?

so im in the middle east and my g70 has a remote start button on the key fob, when i remote start it, the climate settings are set to the state i turned the car off at, so if i want the A/C on when i remote start the car i must turn the car off with the A/C on.

but most people here say its bad for the A/C unit to turn off the car with the A/C on, and im kinda scared to do it lol

 

[YYC Steve]

I’ve seen some discussion on the subject; the concern seemed to be mildew / odours resulting from moisture in the ducting. The thinking was that shutting off AC and running the fan for a short time would ‘dry-out’ the ducting preventing these odours. That’s the only concern I’ve ever heard...and if that’s the case, I suppose you could run with the AC off for a few minutes before shutting down (while the turbos cool down ) and then turn AC on just as you shut it off.

 

[EdP]

hey guys i know this is probably a stupid question but does turning the car off with the A/C on damage it?

so im in the middle east and my g70 has a remote start button on the key fob, when i remote start it, the climate settings are set to the state i turned the car off at, so if i want the A/C on when i remote start the car i must turn the car off with the A/C on.

but most people here say its bad for the A/C unit to turn off the car with the A/C on, and im kinda scared to do it lol

Never heard of that. Bought my first car with AC about 45 years ago and never turned it off No reason too. Pressures will equalize as normal. Ask exactly how and what will be harmed and they won't be able to tell you any details.

 

[joschneider]

My thinking is that the car is already under load during a cold start, why put more stress on it? Yes, the AC will start a couple seconds delayed but the engine is still not even idle at that point. To me, as someone who keeps my car for a long time and also lives in the desert, I wait to turn on my AC. Seems like a small inconvenience in order to potentially prolong something very important to my day to day life. Call it insurance I guess

 

[EdP]

My thinking is that the car is already under load during a cold start, why put more stress on it? Yes, the AC will start a couple seconds delayed but the engine is still not even idle at that point. To me, as someone who keeps my car for a long time and also lives in the desert, I wait to turn on my AC. Seems like a small inconvenience in order to potentially prolong something very important to my day to day life. Call it insurance I guess

What potentially is going to happen? What have you actually seen happen?

True or False: It's OK to Start Car With Accessories Turned On

 

[YYC Steve]

What potentially is going to happen? What have you actually seen happen?

True or False: It's OK to Start Car With Accessories Turned On

I have experienced odours coming from ac system in one vehicle I owned, and it was gross. There are companies charging big $$ to deodorize them. The reported cause is mildew due to moisture buildup. The reported prevention is running system with ac off for a few minutes before shut down.

 

[joschneider]

What potentially is going to happen? What have you actually seen happen?

True or False: It's OK to Start Car With Accessories Turned On

I’ve seen this article, but it doesn’t address my point of concern. The drain on the battery or extra strain from aux power at the exact moment of startup is not something I worry about. When you turn your AC on and idle at a stoplight, what happens? Your fan kicks on, and your idle RPMS raise to compensate. Now imagine that over 1000s of cold starts while your engine is just sitting there with cold, thick oil. That to me, seems like undue stress that the engine doesn’t need and could potentially reduce the life of any number of parts.

 

[tarhoosier]

It sounds to me similar to other stories that may have had a bit of truth to them in the past such as careful of icing the A/C system and use recirculate occasionally, reduce A/C to maintain full power in uphill and high load situations and other concerns from decades ago which have been rectified with the leaps of engineering. Cars built for Middle East and tested in high temperature environments such as the G70 should have no trouble adapting to any action the owner asks of it within the parameters of the owner manual.

 

[Husky]

I have experienced odours coming from ac system in one vehicle I owned, and it was gross. There are companies charging big $$ to deodorize them. The reported cause is mildew due to moisture buildup. The reported prevention is running system with ac off for a few minutes before shut down.

I've experienced that nasty smell in the AC on a couple of my cars over the years. Not sure running the car with the AC off before turning it off would prevent it. How long are you supposed to sit there with it running? In my case I had pretty good luck with an anti bacterial spray that you spray in the ducts. That's probably what the shops do.
In any case, I wonder if it would ever happen in such a dry, arid climate such as the Mideast.

 

[YYC Steve]

I've experienced that nasty smell in the AC on a couple of my cars over the years. Not sure running the car with the AC off before turning it off would prevent it. How long are you supposed to sit there with it running? In my case I had pretty good luck with an anti bacterial spray that you spray in the ducts. That's probably what the shops do.
In any case, I wonder if it would ever happen in such a dry, arid climate such as the Mideast.

Theory was, 5 minutes before you arrive at destination, shut off ac and turn fan to a moderate speed to minimize moisture buildup.
I was thinking the same about lower humidity locations...

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[Mcc]

Now imagine that over 1000s of cold starts while your engine is just sitting there with cold, thick oil. That to me, seems like undue stress that the engine doesn’t need and could potentially reduce the life of any number of parts.

Doesn’t seem like undue stress to me. Seems like an insignificant consequence I don’t even agree that the oil will be cold and thick in warm weather .
i would chalk it up to superstitious behavior.

 

[pulsar]

If Genesis has properly designed the ducting and enclosure for the evaporator coil to drain correctly, odors should not be an issue. Moisture should not get into the ductwork normally for it should condense out and stay in the evap box to drain. I have seen some manufacturers that after engine shut down the ECM runs the A/C fan on low for a minute to attempt to dry this area out. When starting, the compressor will not come on until after engine start so don’t think there is an additional load on the battery or engine for the first few seconds. I’m one who turns everything off before shut down and I turn things back on after startup. Summers in Texas are not here yet for me to remote start to cool the car down to even know how all that is going to work?

 

[EdP]

I have experienced odours coming from ac system in one vehicle I owned, and it was gross. There are companies charging big $$ to deodorize them. The reported cause is mildew due to moisture buildup. The reported prevention is running system with ac off for a few minutes before shut down.

That is possible but it probably is better to make sure the drain is working properly and not gunked up. I don't think a minute or two is enough to really dry the system very well. If you live in a very humid area and add is some organics or bugs from the air it could happen.

 

[Mcc]

Summers in Texas are not here yet for me to remote start to cool the car down to even know how all that is going to work?

Sort of would defeat the use of the remote start to cool down the car
I would put the shutting off a/c before shutting off the car in the same category as those who
don't use the power seats so they don’t wear out
don't use the auto folding mirrors so they don’t wear out
don't use the auto a/c so it doesn’t wear out
Don’t use the power windows so they don’t wear out
until they all freeze and fail from disuse.

 

[EdP]

I’ve seen this article, but it doesn’t address my point of concern. The drain on the battery or extra strain from aux power at the exact moment of startup is not something I worry about. When you turn your AC on and idle at a stoplight, what happens? Your fan kicks on, and your idle RPMS raise to compensate. Now imagine that over 1000s of cold starts while your engine is just sitting there with cold, thick oil. That to me, seems like undue stress that the engine doesn’t need and could potentially reduce the life of any number of parts.

That is your opinion but I've never seen anything to suggest it happens. Every car maker that offers remote start usually offers climate control settings. I'm sure you've seen people here complaining they can't have the heated seats on. That is a potential battery drain at start.
You mention the fan kicking in at idle. That only happens when the system is up at a set temperature, not at start. Cold thick oil? The AC is not used in winter and oil today at 50+ degrees flows pretty good. Especially if the car was run and is not sitting in the sun a half hour at the store when you'd like to have the AC on when you get back in. Think back to cold starting your car with a carburetor and the high idle needed to keep it running at first. That would put more stress in one start that 1000 starts today with the AC engaged.
To each his own, but I like the good climate control we have an just let it do its thing.

 

[EdP]

Sort of would defeat the use of the remote start to cool down the car
I would put the shutting off a/c before shutting off the car in the same category as those who
don't use the power seats so they don’t wear out
don't use the auto folding mirrors so they don’t wear out
don't use the auto a/c so it doesn’t wear out
Don’t use the power windows so they don’t wear out
until they all freeze and fail from disuse.

I used Car Talk as a reference. One question they had was about blinkers. A guy's father would not put his turn signal on until just before he started to turn. His rational was "there are only so many blinks in a blinker and I don't want to wear it out". Forget safety, save that $2 blinker. I did change one once about 50 years ago. None since.

 

[Piz]

Theory was, 5 minutes before you arrive at destination, shut off ac and turn fan to a moderate speed to minimize moisture buildup.
I was thinking the same about lower humidity locations...

I'm not aware that starting your car with the A/C already running is bad for it, but I'm no expert. I'm only here to say the odor thing is real. My 2009 Infiniti G35X would get odors if you didn't blow it out to minimize condensation in the ducts. If you did, the smell went away, but if you didn't the smell would come back quickly. It was a 3 year old CPO, so maybe the previous owner did something to cause it. Either way, this behavior is now ingrained and automatic to me, like Pavlov's dog.

 

[YYC Steve]

Sort of would defeat the use of the remote start to cool down the car
I would put the shutting off a/c before shutting off the car in the same category as those who
don't use the power seats so they don’t wear out
don't use the auto folding mirrors so they don’t wear out
don't use the auto a/c so it doesn’t wear out
Don’t use the power windows so they don’t wear out
until they all freeze and fail from disuse.

Not me. I use ALL of the things. Except the brakes, because wear, and I don’t drive at night to save the headlights

 

[YYC Steve]

I'm not aware that starting your car with the A/C already running is bad for it, but I'm no expert. I'm only here to say the odor thing is real. My 2009 Infiniti G35X would get odors if you didn't blow it out to minimize condensation in the ducts. If you did, the smell went away, but if you didn't the smell would come back quickly. It was a 3 year old CPO, so maybe the previous owner did something to cause it. Either way, this behavior is now ingrained and automatic to me, like Pavlov's dog.

If I remember correctly, it was our ‘04 Maxima that had problems with the same thing. And the solution was the same as yours..