Hi Forum:

I have a 300 SD - 83.. I put in a new compressor, expansion valve.. flushed the A/C lines and plan to refill with freeze 12..

I already have about 700 gr of freeze 12 in the system. It works but I need to top it up and don't seem to be able to find the pressures (high/low side) for R12/Freeze 12.

The system cools reasonable well and plan to increase the amount of freeze 12. Could anybody let me know what pressure I should charge the system to... Currently I have 15 bar on the high pressure side and 2.5 on the low side.

I have the chart for a 124 for R134 and it shows the high pressure should be about 20 bars for the temperature I was evaluating the system (32 deg C.)

How much freeze 12 should I add....

Thanks for your help...

Cheers ....