Switching on Your AC in Cold Start

esteem_lover · 12th September 2006, 23:37

In the morning rush hour, when you start your car for the first time, do you give the engine enough time to heat up & then switch on the AC ? This is one thing most of us fail to do. So let us see which is the majority here. I am giving 4 options here. A.C is switched on after

1. Immediately after start
2. 1-2 Mins after start
3. 4-5 Mins after start or
4. 10 or more Mins after start.

I know, for some of us the whole drive wont be for more than 10 mins. And some of you are living in cold places where you dont need to switch on at all.

Which of these is the best to follow ? experts can pour in with their opinions please.

cheers

naveendhyani · 13th September 2006, 15:35

delhi is too hot

. so i start the car, unlock the parking gate, open it & when i sit back, i turn on the A/C with blower on full blast with the back windows open. keep it like that for 1-2 minutes & then reduce the blower to 1-2 as per requirement & close the windows.

one should always open the rear windows to allow the heated air of the cabin to dissipate resulting in faster & efficient cooling.

pradeepmm · 13th September 2006, 15:54

I read it in the manual (Honda City). Keep the rear windows open and switch on the Blower to the max for around 1 minute. Resulting in pushing the heat air out. Then close the rear windows and switch on the A/C.

Since that all cars have two modes of intake air settings.
1. Intake the air from outside (will take couple of seconds to cool)
2. Circulate the inner air. (this results in faster cooling)

nitrous · 13th September 2006, 16:04

@esteem_lover: No matter how enthusiastic u're about cars, when u live in a place like chennai, u just switch on the AC as soon as the ignition is turned on.
All the blah-blah about engine condition,AC condition isn't much cared for.
Moreover, Synthetic oil always helps keep the engine from wear&tear!

trrk · 13th September 2006, 16:11

Hi,

Quote:

Originally Posted by esteem_lover

1. Immediately after start
2. 1-2 Mins after start
3. 4-5 Mins after start or
4. 10 or more Mins after start.

Unfortunately the four choices do not contain my way.

The AC is permanently on. The car is started with the AC on.

navin · 13th September 2006, 16:15

Quote:

Originally Posted by nitrous

@esteem_lover: No matter how enthusiastic u're about cars, when u live in a place like chennai, u just switch on the AC as soon as the ignition is turned on.
All the blah-blah about engine condition,AC condition isn't much cared for.
Moreover, Synthetic oil always helps keep the engine from wear&tear!

Still Oil does need a few cycles to circulate after an overnight rest.
I'd say 15-30 secs should be enough. After all in hot weather the car is not really that cold!

esteem_lover · 13th September 2006, 16:26

Quote:

Originally Posted by nitrous

@esteem_lover: No matter how enthusiastic u're about cars, when u live in a place like chennai, u just switch on the AC as soon as the ignition is turned on.
All the blah-blah about engine condition,AC condition isn't much cared for.
Moreover, Synthetic oil always helps keep the engine from wear&tear!

very true, especially in the mornings, when you are in a hurry to get started & going, i sweat a lot & if the AC isn't running when iam inside the car, i would drown in my own sweat. LOL

vincentt · 13th September 2006, 17:37

Well there are 2 reasons why I guess you shoudl give it a good gap irrespective of outside temperature, only during a cold start. When I say cold start, I am refering to the start that has to be done, when the car is left overnight in the garage!!! and not when left in the place like outside your office or bank or any other place!!!

There are 2 good reasons for giving a 5 mins gap. ONe the main one being that the engine needs to be kept warm before it is sapped off power because of the AC. This will ensure that the baby is really hot to handle additional load

The second reason being that its a good idea to open your windows and let off all the stale air thats inside the car by opening the windows for a while or two and thus also warming the car on the run!! Then start the blower with outside air to come in, start the AC and let this run for around 20 - 30 seconds and the finally close the outside air vent!! This will keep good the AC and the car.

Exceptions, when you are driving through dust, dont make the mistake of opening the window or runnign blower with outside air in!! Well this is my view and method, it need not be the best. Your comments!!

Knight Rider · 13th September 2006, 19:20

Okay this question is a little bit out of context, But does the blower speed has anything to do with your cars F.E?

MalluDude · 13th September 2006, 19:56

Quote:

Originally Posted by Knight Rider

Okay this question is a little bit out of context, But does the blower speed has anything to do with your cars F.E?

Not at all. Doesn't matter how you keep the blower speed.

supremeBaleno · 13th September 2006, 19:56

It sure does. Higher the blower speed, higher the load on the engine and lower the FE. However, I am not sure whether there are any exact figures as to by how much the FE goes down.

quicksilver · 13th September 2006, 20:15

I normally wait like 10-20 secs before I switch ON the A/C. Have this problem with rolling the windows down that makes me feel "Exposed" and vulnerable some how...

angelfire · 13th September 2006, 21:10

Quote:

Originally Posted by trrk

Hi,

Unfortunately the four choices do not contain my way.

The AC is permanently on. The car is started with the AC on.

Not such a nice thing to do buddy..atleast turn off the AC while startin the car....

Sumed · 13th September 2006, 22:30

It really depend upon the weather. In case weather is really hot and I am in a hurry, I switch on the AC as soon as I start the car... though I do roll down the windows for some time. In case the weather is pleasent, I start the car for a minute and then switch on the AC... Thus voted for the first option.

vivekiny2k · 13th September 2006, 23:08

I roll down all the windows, drive for 30-60 secs, then swich on the AC, keep driving for another 30-60 secs, then roll up the windows.

I like the idea of ventilating my car once a day naturally this way.

View Poll Results: How long do you wait to switch on the AC in your car during a cold start ?
Immediately on starting	52	22.41%
1-2 Mins after start	93	40.09%
4-5 Mins after start	71	30.60%
10 or more Mins after start	16	6.90%
Voters: 232. You may not vote on this poll

12th September 2006, 23:37	#1
esteem_lover Senior - BHPian Join Date: Jul 2006 Location: Madras/Py Posts: 7,556 Thanked: 502 Times View My Garage	Switching on Your AC in Cold Start In the morning rush hour, when you start your car for the first time, do you give the engine enough time to heat up & then switch on the AC ? This is one thing most of us fail to do. So let us see which is the majority here. I am giving 4 options here. A.C is switched on after 1. Immediately after start 2. 1-2 Mins after start 3. 4-5 Mins after start or 4. 10 or more Mins after start. I know, for some of us the whole drive wont be for more than 10 mins. And some of you are living in cold places where you dont need to switch on at all. Which of these is the best to follow ? experts can pour in with their opinions please. cheers Last edited by esteem_lover : 12th September 2006 at 23:44.
	() Thanks

13th September 2006, 15:35	#2
naveendhyani BHPian Join Date: Feb 2006 Location: Melbourne Posts: 542 Thanked: 9 Times	delhi is too hot . so i start the car, unlock the parking gate, open it & when i sit back, i turn on the A/C with blower on full blast with the back windows open. keep it like that for 1-2 minutes & then reduce the blower to 1-2 as per requirement & close the windows. one should always open the rear windows to allow the heated air of the cabin to dissipate resulting in faster & efficient cooling.
	() Thanks

13th September 2006, 15:54	#3
pradeepmm Newbie Join Date: Sep 2006 Location: Bangalore Posts: 2 Thanked: 0 Times	I read it in the manual (Honda City). Keep the rear windows open and switch on the Blower to the max for around 1 minute. Resulting in pushing the heat air out. Then close the rear windows and switch on the A/C. Since that all cars have two modes of intake air settings. 1. Intake the air from outside (will take couple of seconds to cool) 2. Circulate the inner air. (this results in faster cooling)
	() Thanks

13th September 2006, 16:04	#4
nitrous Senior - BHPian Join Date: May 2004 Location: UAE/Lon/Madras Posts: 6,965 Thanked: 325 Times View My Garage	@esteem_lover: No matter how enthusiastic u're about cars, when u live in a place like chennai, u just switch on the AC as soon as the ignition is turned on. All the blah-blah about engine condition,AC condition isn't much cared for. Moreover, Synthetic oil always helps keep the engine from wear&tear!
	() Thanks

13th September 2006, 17:37	#8
vincentt BHPian Join Date: Aug 2006 Location: Bangalore Posts: 70 Thanked: Once	A/c!!! Well there are 2 reasons why I guess you shoudl give it a good gap irrespective of outside temperature, only during a cold start. When I say cold start, I am refering to the start that has to be done, when the car is left overnight in the garage!!! and not when left in the place like outside your office or bank or any other place!!! There are 2 good reasons for giving a 5 mins gap. ONe the main one being that the engine needs to be kept warm before it is sapped off power because of the AC. This will ensure that the baby is really hot to handle additional load The second reason being that its a good idea to open your windows and let off all the stale air thats inside the car by opening the windows for a while or two and thus also warming the car on the run!! Then start the blower with outside air to come in, start the AC and let this run for around 20 - 30 seconds and the finally close the outside air vent!! This will keep good the AC and the car. Exceptions, when you are driving through dust, dont make the mistake of opening the window or runnign blower with outside air in!! Well this is my view and method, it need not be the best. Your comments!!
	() Thanks

13th September 2006, 19:20	#9
Knight Rider BHPian Join Date: Oct 2005 Location: Bangalore Posts: 282 Thanked: 28 Times	Okay this question is a little bit out of context, But does the blower speed has anything to do with your cars F.E?
	() Thanks

13th September 2006, 19:56	#11
supremeBaleno Senior - BHPian Join Date: Dec 2005 Location: Chennai / Kochi Posts: 5,546 Thanked: 2,697 Times View My Garage	It sure does. Higher the blower speed, higher the load on the engine and lower the FE. However, I am not sure whether there are any exact figures as to by how much the FE goes down.
	() Thanks

13th September 2006, 20:15	#12
quicksilver BHPian Join Date: Oct 2005 Location: Coimbatore Posts: 455 Thanked: 12 Times View My Garage	I normally wait like 10-20 secs before I switch ON the A/C. Have this problem with rolling the windows down that makes me feel "Exposed" and vulnerable some how...
	() Thanks

13th September 2006, 22:30	#14
Sumed BHPian Join Date: Sep 2005 Location: Gurgaon Posts: 70 Thanked: Once	It really depend upon the weather. In case weather is really hot and I am in a hurry, I switch on the AC as soon as I start the car... though I do roll down the windows for some time. In case the weather is pleasent, I start the car for a minute and then switch on the AC... Thus voted for the first option.
	() Thanks

13th September 2006, 23:08	#15
vivekiny2k Senior - BHPian Join Date: Feb 2005 Location: cincinnati, jabalpur,chennai Posts: 1,264 Thanked: 209 Times View My Garage	I roll down all the windows, drive for 30-60 secs, then swich on the AC, keep driving for another 30-60 secs, then roll up the windows. I like the idea of ventilating my car once a day naturally this way.
	() Thanks