My 95-S320 A/C is a little low, and tried to recharge the system. But was unable fill freon into the system. I connected both high/low pressure connection, and turn on valves on quick connect. The low pressure was about 30, and the high pressure is about 225.

I am charging the system from the low pressure side, am I doing something wrong?

jack

You should only turn on the low side valve when charging. Be sure to turn on the valve at the gauge as well. This allows the low pressure line and the can to be connected.

. . . monitor your results
 

If the sight glass shows 'bubbles' when the A/C is running, then it might need a charge. If the temp/humidity is high, then a 'few' bubbles are ok.

To monitor the A/C system, check my page (red house) and click on menu #14. Perform the 'Operational Checks' described to check the temps/pressures in the A/C. With the car running, check the evaporator temperature (press REST button five (5) times), sb cycling from 37F to 42F. If so, everythings ok.

[Edited by JimF on 07-23-2001 at 08:29 PM]

update on a/c charge
 

Thank you for the reply, the problem I have put the supply line backward, the needle pressure valve was installed wrong on the menifold, disable freon flow from tank to low pressure connection.

jack