Cycling Aircon

[leonb]

After not using my aircon for about 6 months (winter period), it did not want to work when using it for the first time. So I got it checked out by dealer. They said the compressor could not kick in because of low pressure, and refilled - apparently no leaks.

So it worked, but I could feel that it did not make as cold as when it worked previously.

I let the car idle, put the aircon on coldest setting. I then put my hand on the cold silver/metal part of the aircon pipe (the part that is not insulated in engin compartment), and listen to the the engin. Doing this, I could hear and feel that the comressor is working for about 1 min, then cuts out for about 30 sec, and then kicks in for about 1 min. This cycling continued.

Ambient temps is about 25 deg C. As I said, the air comming from vents is cold, but wen it get very hot (30+ deg C), I can feel the aircon struggling to make car cold fast. It used to be better.

Is this cycling normal? Somewhere I've read about the compressor tripping out of high pressure if the gas was loaded at a too high pressure. Is this a typical symptom?

Also, I read that with adding gas, oil needs to be added. What is this oil, and where is it normally added. What will happen if oil is not added during regas.

The car is a 99 C280.

Thanks