[urq] Airco R12 pressures

[Patrick Carlier]

I've just recharged my AC system with R12 , and I was wondering , does anyone 
know what pressures I should monitor with the airco running ?  


On the high pressure side , it cylces between 120 and 190psi . 
Fan kicking in at 190 psi , causing pressure to drop to 120 . 
At 120 psi , the fan stops and pressure starts to rise again until it 
reaches 190  . 

On the low pressure side it's pretty much stable at 30 psi . 

Does this seem ok ? 
I know it's possible to determine if the system is recharged correctly 
by monitoring the pressures , but I can't remember between wich valuse 
the pressures should be .


I did a compressor rebuild , and changed the dryer for a new one . 
First thing I did was vacuum for half an hour . 
Then rinse the system with dry nitrogen , 12 Bar .  
Then vacuum again for half an hour . 
Finally , I added 800 gramms of R12 by turning the R12 container upside down , and allowing 
liquid gas to enter the high pressure side . This way 600 gramms went in . 
Then I started the engine , with the ac engaged and allowed the compressor to suck in the 
remaining 200 gramms by the low pressure port . WIth the bottle upright , so that gaseous freon was 
fed to the compressor .  


Any comment welcome . 


Pat