Leaving The Car Aircon "On"

[richardjm65]

Maybe this has been addressed before - if so, I can't find it. I read somewhere that it was good to turn off your aircon before switching off the ignition, so that when you next started your engine you would have to turn on the aircon as a secondary action. This, I seem to recall, prevented damage to the aircon and other possible electrical problems. Is this true? Is it likely with a modern car? Any comments?

[transam]

I have never turned it off on any vehicle l have owned when in a hot climate. Some motors have automatic climate control that does it's own thing being computer controlled.

[katabeachbum]

myth

if your battery is almost dead, this is a fix until youv replaced it.

and for the engine, the contrary, engines hate idling when cold, start, load (ac) and go

[MoonRiverOasis]

Oh wow, flashback!

I can remember doing my internship (almost 20 years ago) with an old Scot who'd always lets the company car "warm up" and reach a deathly 65 degrees C inside before turning on the aircon, and then would always turn it back off again 5 mins before we stopped.

I dunno, maybe 40 odd years ago when the first AC units in cars came out all this turning it on/off was somehow valid, but it sure hasn't been valid for at least the past 20 years

[Familyonthemove]

The manual for my Fortuna says the same as the OP posted. Turn off the AC 5 minutes before you switch off the engine. I think it is to help dry out the evaporator to prevent corrosion, mould and bad smells.

I've never actually done this and not have any problems. (apart from the odd bad smell, but that may be me)

[katabeachbum]

in theory cars battery is most able to recieve charge while it is still cold, so for the battery ideally one should run the car for 10 minutes (not idle), before switching on any electrical consumers.

but where I come from headlights and rearlights turns on with engine, and a heater is needed to see anything out of the windshield, and rearwindow defroster and exterior mirror heaters and batteries still live 3-5 years

and the ac interior fan uses same power as one headlight bulb, so use the ac as you please

[MoonRiverOasis]

in theory cars battery is most able to recieve charge while it is still cold, so for the battery ideally one should run the car for 10 minutes (not idle), before switching on any electrical consumers.

Bah, that just sounds like the've under spec'd the alternator or battery

[katabeachbum]

in theory cars battery is most able to recieve charge while it is still cold, so for the battery ideally one should run the car for 10 minutes (not idle), before switching on any electrical consumers.

Bah, that just sounds like the've under spec'd the alternator or battery

thats exactly what most makers do on TH market cars, not hot desert package not cold climate package

[richard_smith237]

I've heard a few while in Thailand...

Turn off your air-con when parking. Always park with the wheels straight.... It seems to be something passed on from friend to friend, generation to generation... There may have been some validity in these beliefs a few years back, but in the modern car these ideals are unnecessary.

I wish many drivers in Thailand would be equally as vigilant when it comes to traffic regulations !

[wandrinstar]

in theory cars battery is most able to recieve charge while it is still cold, so for the battery ideally one should run the car for 10 minutes (not idle), before switching on any electrical consumers.

Bah, that just sounds like the've under spec'd the alternator or battery

thats exactly what most makers do on TH market cars, not hot desert package not cold climate package

Quite so MRO , not often he comes out with daft ideas.Me Thinks hes mixed it up with a Saab Jet Fighter.

[transam]

in theory cars battery is most able to recieve charge while it is still cold, so for the battery ideally one should run the car for 10 minutes (not idle), before switching on any electrical consumers.

Bah, that just sounds like the've under spec'd the alternator or battery

thats exactly what most makers do on TH market cars, not hot desert package not cold climate package

Quite so MRO , not often he comes out with daft ideas.Me Thinks hes mixed it up with a Saab Jet Fighter.

They have Boliden batteries.

[MJo]

Very common in Philippines for taxis to turn off their lights when stopping for a red light. Saves the bulbs you know. Some also stop the engine to save fuel. Horns seems to be cheap down there as they all use it in every street corner even 5am in the weekends when there is no one around...

[MESmith]

if your battery is almost dead, this is a fix until youv replaced it.

Problem is the battery doesn't always tell you when it's almost dead. The first signs I get the battery is on its way out, I'm not sure it would have started with the ac on. Always turn my ac off after the engine. Switch it on immediately after start up. Where I live there's no one close by to connect jumper cables to.

[thaiIand]

we could send ppl on the moon 40yrs ago so srsly if cars by now cant function correctly without having to close the AC 5mins before... well

[MoonRiverOasis]

Very common in Philippines for taxis to turn off their lights when stopping for a red light. Saves the bulbs you know. Some also stop the engine to save fuel. Horns seems to be cheap down there as they all use it in every street corner even 5am in the weekends when there is no one around...

555.

It's a bit like how Malaysian Proton drivers open their doors to pay tolls, becuase the electric windows only go up and down 10 times before failing. That one's true though

[BSJ]

Don't worry about it. With all the current heading to the starter motor there probably isn't enough to energize the compressor solenoid. Once running the idle up device will set your idle slightly higher to compensate for the load when the compressor solenoid does kick in.

[wandrinstar]

Once started they run of the Alternator , not the Battery , that ended when dynamo / magneto charging ended ...I still find Climate Conroll a mystery , ive got it, the book says so , but its the same as a Jazz to me , just Cold , Very Cold or Warm , more useless gizmoes.

[DJH77]

The manual for my Fortuna says the same as the OP posted. Turn off the AC 5 minutes before you switch off the engine. I think it is to help dry out the evaporator to prevent corrosion, mould and bad smells.

I've never actually done this and not have any problems. (apart from the odd bad smell, but that may be me)

Car electrics are far stronger today than in the 60's and 70's. the turn off routine was just to make it easier to restart the motor. As for the bad smell from the evaporator, the old way to cure this was to pull it out and give it a good clean and wash it in Vinegar.

[katabeachbum]

I've heard a few while in Thailand...

Turn off your air-con when parking. Always park with the wheels straight.... It seems to be something passed on from friend to friend, generation to generation... There may have been some validity in these beliefs a few years back, but in the modern car these ideals are unnecessary.

I wish many drivers in Thailand would be equally as vigilant when it comes to traffic regulations !

at least 20% of pickupdrivers open their hood at 7eleven or lunchbreaks along highways

[katabeachbum]

The manual for my Fortuna says the same as the OP posted. Turn off the AC 5 minutes before you switch off the engine. I think it is to help dry out the evaporator to prevent corrosion, mould and bad smells.

I've never actually done this and not have any problems. (apart from the odd bad smell, but that may be me)

Car electrics are far stronger today than in the 60's and 70's. the turn off routine was just to make it easier to restart the motor. As for the bad smell from the evaporator, the old way to cure this was to pull it out and give it a good clean and wash it in Vinegar.

the new cure is to spray it with 3M. I do it twice a year, kills all bugs and funghi. also spray the ac ducts. and ac becomes more efficient

my maid does all the ac in my home every second month

[PattayaParent]

in theory cars battery is most able to recieve charge while it is still cold, so for the battery ideally one should run the car for 10 minutes (not idle), before switching on any electrical consumers.

but where I come from headlights and rearlights turns on with engine, and a heater is needed to see anything out of the windshield, and rearwindow defroster and exterior mirror heaters and batteries still live 3-5 years

and the ac interior fan uses same power as one headlight bulb, so use the ac as you please

It wouldn't be the fan using up the power it would be the AC compressor.

I remember when working in UAE 30 years ago one of my colleagues had an old yank car and we were heading out to Bani Yas one day and when he needed to accelerate to pass anything on the highway he would have to turn the AC off.

The power surge pushed you back into the seat but when the AC went on again the car almost died.

I hardly need to use the AC here in Thailand, just drive with the window open most days.

[transam]

The older type compressors were internal multi-piston, belt driven by the engine and used a lot of engine power, newer design are rotary and use less power. BUT if the A/C is turned on on start up there is a delay after start up for the clutch on the compressor to energize the system, the clutch is electrically operated, so there is no engine power loss on start up as the clutch pulley is free wheeling.

[funcat]

Car electrics are far stronger today than in the 60's and 70's. the turn off routine was just to make it easier to restart the motor. As for the bad smell from the evaporator, the old way to cure this was to pull it out and give it a good clean and wash it in Vinegar.

the new cure is to spray it with 3M. I do it twice a year, kills all bugs and funghi. also spray the ac ducts. and ac becomes more efficient

my maid does all the ac in my home every second month

What 3M product is it and where to buy ?..thanks

[sonic_11uk]

Car electrics are far stronger today than in the 60's and 70's. the turn off routine was just to make it easier to restart the motor. As for the bad smell from the evaporator, the old way to cure this was to pull it out and give it a good clean and wash it in Vinegar.

the new cure is to spray it with 3M. I do it twice a year, kills all bugs and funghi. also spray the ac ducts. and ac becomes more efficient

my maid does all the ac in my home every second month

What 3M product is it and where to buy ?..thanks

Sorry to bring an old thread back to the top but I too was wondering what 3M product (or similar) product is used to clean the filters and kill bacteria/fungi.

Cheers!!!

[watcharacters]

Very common in Philippines for taxis to turn off their lights when stopping for a red light. Saves the bulbs you know. Some also stop the engine to save fuel. Horns seems to be cheap down there as they all use it in every street corner even 5am in the weekends when there is no one around...

Amen.

Horns seems to be cheap down there as they all use it in every street corner even 5am in the weekends when there is no one around

[JAS21]

I've heard a few while in Thailand...

Turn off your air-con when parking. Always park with the wheels straight.... It seems to be something passed on from friend to friend, generation to generation... There may have been some validity in these beliefs a few years back, but in the modern car these ideals are unnecessary.

I wish many drivers in Thailand would be equally as vigilant when it comes to traffic regulations !

at least 20% of pickupdrivers open their hood at 7eleven or lunchbreaks along highways

And do you know why? It's not only pick up trucks that do it.

Thinking about it he probably doesn't care now anyway.........................

Edited July 20, 2012 by JAS21

[Woodsie888]

Car electrics are far stronger today than in the 60's and 70's. the turn off routine was just to make it easier to restart the motor. As for the bad smell from the evaporator, the old way to cure this was to pull it out and give it a good clean and wash it in Vinegar.

the new cure is to spray it with 3M. I do it twice a year, kills all bugs and funghi. also spray the ac ducts. and ac becomes more efficient

my maid does all the ac in my home every second month

What 3M product is it and where to buy ?..thanks

Sorry to bring an old thread back to the top but I too was wondering what 3M product (or similar) product is used to clean the filters and kill bacteria/fungi.

Cheers!!!

The fella that suggested the 3M product is no longer in a position to answer your question. He has a bit of a problem to sort out first.

Go to any of the A/C service centres that are about and they'll sell you a deodoriser/anti funghi spray. It doesn't have to be 3M to achieve your desired result.

Edited July 21, 2012 by Woodsie888

[BangkokMatt]

I was just about to post a topic in reference to this subject.

I have a 1 week old brand new Pajero Sport. If the Aircon is on whilst the car is stationary it pours out water from middle of the underside. I have taken it into Mitsubishi and they have said that this is 'normal and a good thing'.

I'm not sure I believe them. Can anyone advise me please.

Cheers all

Matt

[transam]

I was just about to post a topic in reference to this subject.

I have a 1 week old brand new Pajero Sport. If the Aircon is on whilst the car is stationary it pours out water from middle of the underside. I have taken it into Mitsubishi and they have said that this is 'normal and a good thing'.

I'm not sure I believe them. Can anyone advise me please.

Cheers all

Matt

It's normal and shows all is working fine.

[BangkokMatt]

Thanks Transam. It doesn't look normal to me but I don't know much about the mechanical side of things.

It's good to get your advise