A/C on by default?

GBX · 11-06-2008, 12:48 PM

Quote:

Originally Posted by seanl

BTW, if I turn off the a/c compressor manually, next time I turn on the climate control fans the a/c compressor stays off. Interesting.

Really, mine comes on, but i press auto to turn the system back on. Are you just pressing the fan?

ncoig · 11-06-2008, 03:15 PM

Quote:

Originally Posted by E92_328i_Boston

Having your A/C on and the temp set to the hottest will not be any cooler than the temp set to the hottest with the A/C off, will it?

-A

I would think it would be, because it's mixing cooler air than outside air with the same temp (max) of air across the heater core.

More to the point, the air will be drier and FEEL cooler.

-N

ncoig · 11-06-2008, 03:15 PM

Quote:

Originally Posted by seanl

BTW, if I turn off the a/c compressor manually, next time I turn on the climate control fans the a/c compressor stays off. Interesting.

B/C you're disabling the "AUTO" functionality of the compressor.

I think.

-N

Wires · 11-07-2008, 10:20 AM

Not sure what the issue is. If you have it in "auto" mode, then you want the car to keep a set temperature, no?

So if it needs A/C to drop the cabin temp, it does so. If it needs heat to raise it, then it does. Just because the A/C light is on, doesn't mean the compressor is running. A/C light doesn't = cold air. Just means that it's enabled to turn on when it needs to.

But like said above, 99.9% of the vehicles will cycle the A/C compressor with the defrost on just to lubricate the seals. Otherwise you end up with a car like in the 80's where nothing but warm blows in the summer since the seals dried out and the freon leaked out.

seanl · 11-07-2008, 10:59 AM

Quote:

Originally Posted by GBX

Really, mine comes on, but i press auto to turn the system back on. Are you just pressing the fan?

Yes

ElRedOne · 11-07-2008, 12:44 PM

Most automobile systems disable the compressor when the outside temperature appoaches freezing. I believe the compressor remains engaged even if not needed (i.e. 50 degrees), but stays off at 37 or so and below.

ncoig · 11-07-2008, 01:28 PM

Quote:

Originally Posted by ElRedOne

Most automobile systems disable the compressor when the outside temperature appoaches freezing. I believe the compressor remains engaged even if not needed (i.e. 50 degrees), but stays off at 37 or so and below.

I think this is true. Not sure about the Bimmers, but my truck always switches on the compressor for the defroster unless it's below about 37, then it is disabled.

-N

11-07-2008, 10:20 AM	#26
Wires Major General 1838 Rep 5,171 Posts Drives: 2016 340i xDrive Join Date: Apr 2008 Location: Calgary iTrader: (0)	Not sure what the issue is. If you have it in "auto" mode, then you want the car to keep a set temperature, no? So if it needs A/C to drop the cabin temp, it does so. If it needs heat to raise it, then it does. Just because the A/C light is on, doesn't mean the compressor is running. A/C light doesn't = cold air. Just means that it's enabled to turn on when it needs to. But like said above, 99.9% of the vehicles will cycle the A/C compressor with the defrost on just to lubricate the seals. Otherwise you end up with a car like in the 80's where nothing but warm blows in the summer since the seals dried out and the freon leaked out.
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11-07-2008, 12:44 PM	#28
ElRedOne First Lieutenant 3 Rep 303 Posts Drives: '06 330xi, '06 Z4M Join Date: Oct 2007 Location: PA iTrader: (0)	Most automobile systems disable the compressor when the outside temperature appoaches freezing. I believe the compressor remains engaged even if not needed (i.e. 50 degrees), but stays off at 37 or so and below. __________________ ElRedOne 330 xi Electric Red/Beige Step-Premium-Sport-CW-CA-PDC-Shade Z4MR Interlagos/Black
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