Evening everyone.

When it comes to aircons electrically and mechanically i know how they work and how to fix them but the aircon charging remained a bit of a mistery. Untill i read the ultimate DIY thread.

I have purchased a dual low/hig pressure gauge with the small cans of R134a to charge my C5 aircon myself.

This evening i hooked up the gauge, and i got these readings:

25psi low pressure side
245psi high pressure side.
60° center duct temperature
70° outside air temperature
relative air humidity was around 80%

in fact it was a cold, wet day today, probably not ideal for testing an aircon


Now after having taken these readings i have 3 big questions

- do these readings seem normal is my aircon undercharged? I don't really know how the map in the DIY thread is supposed to be read.

Is the ambient temperature on the chart to be taken as reference. In that case i should read 30psi low side, 190psi high side and 50° center duct temperature.


- how long does it take for a can to be completely transferred into the system. Will it be completely empty when it is? How do i know when to stop?

- center duct temperature, is this the temperature measured at the center front air outlet grill inside the car. (aircon is at lowest and highest fan speed)


Sorry for these beginner questions, i really want to get my head around this.

Many thanks, Xavier.