: a/c compressor on and off in wintertime with heater on?



ocjmakaveli
11-19-04, 03:53 PM
my a/c compressor cycles on and off every once in a while althoughits cold outside and i have the heater on I wonder about this cause none of my other cars ever do this with the heater on i usually have it at 74 or 78 but it still cycles i can only hear it when im parking etc. usually its too low of a sound but i can tell it cycles on and off.is this unusual?

luddyludwick
11-19-04, 04:00 PM
No. Actually, it means your climate control system is working properly.

The climate control system on our Cadillacs is programmed to 1) maintain the temperature you select, and 2) maintain a "comfortable" humidity level. As you know, a/c takes humidity out of the air. The cc is just turning on the compressor so that it can eliminate some humidity.

If you put it on front defrost/defog, it's going to keep the compressor in default on (other than normal cycling). If you don't want the compressor on ever when it's cold out, etc., just push the "Econ" button. It will maintain whatever temperature you desire, but just keep the compressor off. This might get your windows fogged up a little bit, but other than that, nothing out of the ordinary.

Hope this helps.

scurling
11-19-04, 04:08 PM
This is normal for the automatic a/c units in our Fltwds. The compressor in the H-A/C is always working based on the temperature setting in the car unless you push the ECON button. The ECON[omy] button basically turns off the compressor. You must keep in mind that these systems are meant to be "Automatic", thereby they don't provide all the controls we may be use to with other cars. I personnally do not like the automatic system in the Fltwd., but that's what we are stuck with.

From the manual:
This switch provides an input to the H-A/C control, which controls the A/C compressor. Touching the ECON switch wil interupt the A/C request signal to the PCM. This prevents the added fuel consumption caused be the power drag of compressor operation. AUTO or DEFROST must be selected to reactivate the compressor assembly.

ocjmakaveli
11-20-04, 12:59 AM
No. Actually, it means your climate control system is working properly.

The climate control system on our Cadillacs is programmed to 1) maintain the temperature you select, and 2) maintain a "comfortable" humidity level. As you know, a/c takes humidity out of the air. The cc is just turning on the compressor so that it can eliminate some humidity.

If you put it on front defrost/defog, it's going to keep the compressor in default on (other than normal cycling). If you don't want the compressor on ever when it's cold out, etc., just push the "Econ" button. It will maintain whatever temperature you desire, but just keep the compressor off. This might get your windows fogged up a little bit, but other than that, nothing out of the ordinary.

Hope this helps.

thx a million i knew it wasnt the compressor cause the air conditioning works fine thx again scurling too just wondering why it did this.

scurling
11-20-04, 02:21 AM
Looks like Ludwick and I were responding at the same time. You know what they say, "Great minds think alike", but greater minds think alike and at the same time.

cl1986
12-05-04, 09:30 PM
all cars do this when in defrost mode, it removes ice and snow faster off of a windheild.

White Whale
12-06-04, 11:15 AM
Other cars also run the A/C pump on "defrost" to keep the A/C system lubed up in order to avoid a nasty suprise when you turn the A/C on when it gets hot outside.