[noopster]

Haven't we seen in enough Hollywood movies and pulp novels that attaching a pipe to the exhaust and slipping it into the car with the engine on, and then rolling up the windows fully is a certain way to a painless suicide? Carbon monoxide present in the exhaust fumes in normal concentrations when vented properly is not fatal but in the confines of a small vehicle, can be. Ironically, it's the fact that the AC is on fresh setting that would increase the chances of this happening. However as vina and others state, the probability of CO poisoning being cause of death in this case seems remote.

I would never advise anyone to sleep in a car with the engine on. Forget asyphxiation, what if you hit something in your sleep and the vehicle rolls onto the road or worse OFF it? I believe it is illegal to sleep in a running car in the US (someone please confirm). My advice: plan your trip such that you never have to sleep in the car, or at least take turns, use recirculation mode wisely (VW reccomends not more than 10 minutes at a time!), find a motel if you are sleepy, or worst case- take a power nap of not more than 15-20 minutes with the engines off.

[lloydofcochin]

This is very concerning and is an eye-opener for me

I have slept in the Car umpteen number of times with the AC on and in re-circulation mode. I have hardly used the fresh air mode. It has been used only in hilly areas where the air is really fresh.

While on night drives I usually take 2-3 power naps ranging from 15-20 mins with the engine running and AC on. The only exception was when I slept with the windows open for an inch or so on my friend's U/VA since it was a Petrol Car

3-4 months back my relative-in-law got in to his Car to take a nap. He wanted to turn on the engine and the AC but since he was too tired he dozed off immediately. He had instructed his workers to wake him up after 2 hours. They knocked on the window and he woke up but appeared lost and was struggling to unlock the Car from inside. They waited for 2-3 mins and gestured him to open the door but he was struggling like a lost man and at the moment they felt that something was amiss and broke the rear window glass of his SX4 and when the much needed oxygen entered the Car he was back to his senses.

Anyways I have decided on not to sleep in the Car with the AC on when I'm alone and also to use the fresh air mode quite often to ensure that the stale air is dumped from the Car.

[nozzlering]

Originally Posted by alpha1

WHY will heating coil produce CO on its own, when I engage the heater circuit on?

It won't. Heater is only transferring the heat to the air being passed through it. CO wont be produced by the ac or due to respiration by occupant/s. Actually, in lack of oxygen, the comustion process inside the car's engine will produce CO. And eventually this gas might creep into the car cabin.

[ventolute]

Just read an article online . How much truth is there to it?
http://thetruthoflife-hazirah.blogsp...ately.html?m=1
Same article on another page
http://www.godlikeproductions.com/fo...age1378375/pg1

[vina]

Originally Posted by ventolute

Just read an article online . How much truth is there to it?
The Truth Of Life...: Do not Turn on Car A/c Immediately
Same article on another page
Read before you turn on your Air CONDITIONER!!!!

This has nothing to do with AC.

Even if you have no intention of turning on the AC, it is a good idea to open the windows for a few minutes and get in some fresh air.

[GTO]

A 37 year old Techie was found dead in his air-conditioned car : Link

[nandans2005]

Does it help to keep the windows glass rolled down a little bit when the car is parked ? Would the air circulation reduce the toxin levels at all ?

[devsoftech]

In first place, I despise of sleeping in car with A/C for following reasons:

a. Ergonomics/comfort and not a natural sleep - And no match for a sleep in a bed. I do not have a A/C at home (thanks to bangalore weather), but I'm pampered by the comfort of an A/C - But I will never sleep in a car to get the advantage of an A/C. Its ironical that I paid 20-22k for A/C (price included in a car), yet did not think of having a separate A/C at home. A/C is a luxury to be enjoyed, but car is a very wrong place. It is better to invest in a A/C for a room where u want to take a break and enjoy a 'nap'. Particularly I would advise this to my real estate friends, who sleep in their SUVs during a site visit. Please build a room with A/C and add a bed, won't cost you very much. (even visitors will appreciate)

b. Not good for environment at the cost of emissions. The energy generated is not efficient as most of it is wasted in idling (not for 100% A/C)
c. Taxes your engine as it idles.
d. You are vulnerable to theft
e. At times, you might be wasting 'precious' space.

However, if you happen to have a "life on wheels", guess open sunroof should help in such cases:
1. Hot air escapes from top, reducing load on A/C
2. Fresh natural air is always available. (so a/c in recirculation is not a big deal)
3. Reduces the claustrophobia in car.
4. Wind/external noise will delay your sleep compared to a closed and confined setup.
5. You can still keep windows closed (reduced risk of theft).

[R2D2]

Sleeping in a car with the windows rolled up and the AC on is asking for trouble. Bad for the environment, bad for you. Why not rent a hotel room for a night instead of sleeping in the ca,r better still go home?

If you have an exhaust system leak and gases seep into the cabin it is only a matter of time before you are asphyxiated. You won't even know you are falling short of oxygen when you are fast asleep in the car.

[gopa99]

i was told by an ac expert that even in the recirculation mode of acs, there is a 10 to 20% mixing of fresh air forced by the gating mechanism. Probably it might not be the case considering the instances sited. wondering why the car manufacturers never took this into account while designing hvacs. and what about a 2nd tier or 3rd tier on indian railways ac coaches. imagine 72 snoring people pumping carbon dioxide into a closed cabin with recirculated ac draft, dealdy then!

[sdmn]

I've followed a simple technique all these years with all cars I've owned.

1. City: Default recirc mode with occasional fresh air mode if the drive lasts longer than half an hour. Sometimes, instead of switching to fresh air mode, I find it more convenient to open both front windows by 1 inch for some 20 secs. I also feel that brings in a larger volume of fresh air.

2. Highways: Default fresh air mode with switching to recirc only in dusty or smelly stretches.

I do feel though that the law must mandate a beep / alarm after the recirc has been enabled for more than 30 mins, even in the manual non electric / non ACC models.

[vina]

Originally Posted by GTO

A 37 year old Techie was found dead in his air-conditioned car : Link

report says the air inside the car was hot, so cops are not even sure AC was on. And CO doesn't kill this fast unless someone is trying to kill you.

More likely the guy had a seizure as is being suspected.