Aircon always on, or on/off
07-03-2011, 01:19 PM
#1
Burning Brakes
Thread Starter
Aircon always on, or on/off
Question for the gang: now we're deep into summer time (esp in Atlanta) do you keep your a/c running the whole time, or turn it off a minute or two before shutting down the engine?
I've always been told to turn he compressor off before pulling into the parking space, to allow non-condensed air to flow through the ductwork. Is this really beneficial? Is it ok to be starting the car with a/c already engaged?
Was just wondering if any benefit is outweighed by switching the compressor on and off.
Thanks!
I've always been told to turn he compressor off before pulling into the parking space, to allow non-condensed air to flow through the ductwork. Is this really beneficial? Is it ok to be starting the car with a/c already engaged?
Was just wondering if any benefit is outweighed by switching the compressor on and off.
Thanks!
07-03-2011, 01:26 PM
#2
I usually hit the eco button to turn the compressor off a couple of blocks before getting home. I read somewhere it gives some parts time to dry off a bit before shutting the car off. Not sure if it's true or not, but I don't have any issue with that musty smell the many cars develop from running the ac in the summer. Having the compressor off during start up puts less load on the starter, but I don't imagine that's really an issue for motors these days.
07-03-2011, 03:03 PM
#4
Nordschleife Master
It's always best to start an engine with the least amount of parasitic loads. So... turn the AC on (Auto button) after starting the engine.
AC should also be used during Winter. It dries the air preventing window fogging and keeps the compressor fit avoiding dried out seals. Just regulate your cabin temp accordingly (like 70F or higher).
07-03-2011, 04:22 PM
#6
Burning Brakes
The compressor cycles on and off as needed during normal use to reduce the load on the engine and save gas. The ECU turns the compressor off during start up so don't worry about manually turning it off.
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07-04-2011, 01:39 PM
#9
Drifting
That is the way to dry duct work and avoid fungii. It should be turned off a couple of miles before stopping, keeping vent on high to dry things up.
It's always best to start an engine with the least amount of parasitic loads. So... turn the AC on (Auto button) after starting the engine.
AC should also be used during Winter. It dries the air preventing window fogging and keeps the compressor fit avoiding dried out seals. Just regulate your cabin temp accordingly (like 70F or higher).
It's always best to start an engine with the least amount of parasitic loads. So... turn the AC on (Auto button) after starting the engine.
AC should also be used during Winter. It dries the air preventing window fogging and keeps the compressor fit avoiding dried out seals. Just regulate your cabin temp accordingly (like 70F or higher).
I have a switch mounted on the back wall of the Odments box that I use to open the AC compressor circuit except of cooling use. I also have a water valve in line with the heater core to bypass the reheat/remix process during the summer months. AC is much more efficient, improved MPG and less heat load on the coolant system.
The best way I have found to prevent the growth, breeding, of the microbes whose "leavings" constitute that mold and mildew odor is to leave the windows slightly down each and EVERY night.
Go to airsept.com and read up on their EED, Electronic Evaporator Dryer.
"...AC should also be used during winter.."
Absolutely NOT, NEVER..!!
As of yet we have no way of predicting when or if use of the AC for dehumidification during cold weather will be efficient enough to be of benefit, that's why your Porsche will ALWAYS throw maximum heating to the windshield airflow when you switch to defrost/defog/demist mode.
The DANGER in use of the AC during the cooler times is that it will be automatically switched off should the OAT decline below ~34F. Once switched off the evaporator surface area temperature will begin to rise therefore beginning the evaporative process for the thin film of condensate always present on an operating evaporator.
Cabin Rh begins to climb accordingly....
Sudden episodes of windshield/window fogging often results.
07-04-2011, 03:00 PM
#10
Nordschleife Master
...
"...AC should also be used during winter.."
Absolutely NOT, NEVER..!!
As of yet we have no way of predicting when or if use of the AC for dehumidification during cold weather will be efficient enough to be of benefit, that's why your Porsche will ALWAYS throw maximum heating to the windshield airflow when you switch to defrost/defog/demist mode.
The DANGER in use of the AC during the cooler times is that it will be automatically switched off should the OAT decline below ~34F. Once switched off the evaporator surface area temperature will begin to rise therefore beginning the evaporative process for the thin film of condensate always present on an operating evaporator.
Cabin Rh begins to climb accordingly....
Sudden episodes of windshield/window fogging often results.
"...AC should also be used during winter.."
Absolutely NOT, NEVER..!!
As of yet we have no way of predicting when or if use of the AC for dehumidification during cold weather will be efficient enough to be of benefit, that's why your Porsche will ALWAYS throw maximum heating to the windshield airflow when you switch to defrost/defog/demist mode.
The DANGER in use of the AC during the cooler times is that it will be automatically switched off should the OAT decline below ~34F. Once switched off the evaporator surface area temperature will begin to rise therefore beginning the evaporative process for the thin film of condensate always present on an operating evaporator.
Cabin Rh begins to climb accordingly....
Sudden episodes of windshield/window fogging often results.
07-06-2011, 04:52 AM
#11
Nordschleife Master
rarely a need for AC - love SF weather
07-06-2011, 08:57 AM
#12
Rennlist Member
Now I've gotta go read my manual. Out of town right now though. How do you turn the AC on/off?
07-06-2011, 12:35 PM
#13
Drifting
There is basically no way to turn it off FULLY. Use the provided control to turn it off and it will still "function" in defrost/defog/demist mode and then when it subsequently switches off you will be in danger of encountering an instant of sudden windshield fogging.
07-06-2011, 12:42 PM
#14
Three Wheelin'
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With the evaporator vane surface area's operational temperature as low as 34F it can easily take up to an hour for the plenum temperature to rise high enough for that thin film of condensate to begin evaporating off those vanes. And then where is it to go...into the cabin if the windows are fully closed.
I have a switch mounted on the back wall of the Odments box that I use to open the AC compressor circuit except of cooling use. I also have a water valve in line with the heater core to bypass the reheat/remix process during the summer months. AC is much more efficient, improved MPG and less heat load on the coolant system.
The best way I have found to prevent the growth, breeding, of the microbes whose "leavings" constitute that mold and mildew odor is to leave the windows slightly down each and EVERY night.
Go to airsept.com and read up on their EED, Electronic Evaporator Dryer.
"...AC should also be used during winter.."
Absolutely NOT, NEVER..!!
As of yet we have no way of predicting when or if use of the AC for dehumidification during cold weather will be efficient enough to be of benefit, that's why your Porsche will ALWAYS throw maximum heating to the windshield airflow when you switch to defrost/defog/demist mode.
The DANGER in use of the AC during the cooler times is that it will be automatically switched off should the OAT decline below ~34F. Once switched off the evaporator surface area temperature will begin to rise therefore beginning the evaporative process for the thin film of condensate always present on an operating evaporator.
Cabin Rh begins to climb accordingly....
Sudden episodes of windshield/window fogging often results.
I have a switch mounted on the back wall of the Odments box that I use to open the AC compressor circuit except of cooling use. I also have a water valve in line with the heater core to bypass the reheat/remix process during the summer months. AC is much more efficient, improved MPG and less heat load on the coolant system.
The best way I have found to prevent the growth, breeding, of the microbes whose "leavings" constitute that mold and mildew odor is to leave the windows slightly down each and EVERY night.
Go to airsept.com and read up on their EED, Electronic Evaporator Dryer.
"...AC should also be used during winter.."
Absolutely NOT, NEVER..!!
As of yet we have no way of predicting when or if use of the AC for dehumidification during cold weather will be efficient enough to be of benefit, that's why your Porsche will ALWAYS throw maximum heating to the windshield airflow when you switch to defrost/defog/demist mode.
The DANGER in use of the AC during the cooler times is that it will be automatically switched off should the OAT decline below ~34F. Once switched off the evaporator surface area temperature will begin to rise therefore beginning the evaporative process for the thin film of condensate always present on an operating evaporator.
Cabin Rh begins to climb accordingly....
Sudden episodes of windshield/window fogging often results.
07-06-2011, 02:50 PM
#15
Nordschleife Master
So you agree that the AC should be used to defog... after all the factory programs it to do so. In my humble experience AC and a bit of heat works perfectly during the winter.