should the A/C compressor be on all the time when set to min?

Post by **Clemens** » 24 Feb 2016, 13:41

Hi!

THe other day I thought I´d use the A/C a bit so it won´t seize. Themperature was in the range of 55-60 degrees. The compressor came on and off while driving which is normal, I´d say if the exterior temp is lower than the interior temp. But then I set both climate control knobs to min, opened the hood and expected the compressor to run all of the time. But it came on for a few seconds, then off for a few, then back on.

Keeps me wondering: Is taht normal even if the AC is set to min? Or is this an issue with the clutch gap or am I in Need of an AC Service/refill?

It worked alright last year.

Btw, it´s a 96 855 R.

Post by **tryingbe** » 24 Feb 2016, 15:01

Measure the gap.
Measure the pressure in the system.

Those are the only two accurate way to tell.

Post by **oragex** » 24 Feb 2016, 15:03

That's how it works, it's cycling, the compressor doesn't work continuously.

Post by **polskamafia mjl** » 25 Feb 2016, 09:41

A little beside the point but the compressor will also come on to defrost the windshield. So if you've been using the defrost function during the winter you don't need to worry about the compressor seizing.

Post by **Clemens** » 25 Feb 2016, 13:46

Thanks for the input. Today I did some testing and it seems like the System pressure is too low. So I guess I´ll Need a refill at least. Hopefully not the evap.

Speaking of the devil (evap): anyone ever tried to fix a bad evap with some sorta AC sealant? Given the hassle of taking all that apart (and putting it back together correctly) it might be worth a try.

Post by **abscate** » 25 Feb 2016, 14:21

Using sealant is 1000 USD roulette. The orfice tube on these systems is small and it is easy to plug.

The only fix for leaking AC is replacing bad parts ..in this case almost certainly the evap.

Post by **misha** » 25 Feb 2016, 15:40

polskamafia mjl wrote:A little beside the point but the compressor will also come on to defrost the windshield. So if you've been using the defrost function during the winter you don't need to worry about the compressor seizing.

No it will not if outside temperature is below 2 degrees Celsius.

Post by **misha** » 25 Feb 2016, 15:43

oragex wrote:That's how it works, it's cycling, the compressor doesn't work continuously.

In the summer temperatures,when system is properly charged and pressures ok,compressor will run all the time without cycling.
It starts cycling when refrigerant level drops,or when outside temperatures are colder.

Post by **polskamafia mjl** » 25 Feb 2016, 21:11

misha wrote:
polskamafia mjl wrote:A little beside the point but the compressor will also come on to defrost the windshield. So if you've been using the defrost function during the winter you don't need to worry about the compressor seizing.
No it will not if outside temperature is below 2 degrees Celsius.

You may be right, Misha, although I've never heard that before but it does surprise me. Where did you read that?

Post by **misha** » 26 Feb 2016, 01:04

No need to read...try it and you will see.

That's a protection for ac compressor from seizing.