I simply write down what happened with my aircon system in the 2003 S55 Kompressor to see or somebody got answers for me as I and the air conditioning "Specialist " are at a lost.
1 year ago aircon compressor packed up.(Seals failed and all gas laked out - dye visible) Replaced together with strainer, gassed up 950 gr R134, reset the system and all well.
This year on long trip holidays after 4000km suddenly red aircon light game on and no cooling. Reset can be done but the fault came back.
I suspected compressor failure again. Went to specialist. Hooked up gauges and there was still gas in system. We reset the system via dash unit. Then they hooked up a Robinair Auto-aircon system which recovers first the remaining gas (Only 250 gr came out), vacuums, reinserts oil and dye and then auto re-gassed the system (770 gr) in a computer controlled way. Started the car and the system ran and cooled but suddenly the HP pressure gauge on the Robinair unit started to rise and rise and since the aircon guy did nothing it ran of the scaled (over 40 bar). Suddenly somewhere near the compressor we heard an "Explosion" and a vapour escaped. (White smoke). I thought that now a pipe had burst and quickly the operator shut down the car and the Robinair unit. (HP gauge would however not go back to zero). We checked for massive dye deposits but found little (Special light). It was decided to restart the Robinair unit and started the whole process from scratch. (recover gas (All came out - 800 gr), oil & dye) reinsert oil and dye and charged gas but now only 350 gr as we were afraid for overcharging. Started up the car and system ran fine with stable LP & HP readings and cooling going down to 12 degree C. We then twice added 50gr gas (total now 450) and decided to leave it there afraid for more trouble. System is now running for a week and cools fine, copes. (Ambient with us in North South Africa +35-40 degree C at the moment. We are theoretically 1050 (double system gr. gas requirement) - 450 = 600 Gr short (must thrust Robinair system printout) but it works. I (We) are at a total lost what happened with this massive pressure rise in the first place and with the system as a whole. (Perhaps the system suddenly blocked and with the super pressure it unblocked??) Perhaps somebody can tell us what they think what happened and what to do, to get it right.