i had my lines disconnected since winter time when i replaced my heater core in my 02 4.7 ram 1500 its now the beginning of july and im getting to putting the lines back on but i noticed that when i did the heater core i broke the ac core line so i used rubber tubing and clamped it to the core and then the expansion chamber i did blow air through to see if there was any blockage it came through fine. But when i went to fill up just 12oz of r134a i blew off my bigger ac line i think its the high pressure line....what would cause this to happen i do know the compressor is bad you can hear it squeal but it does engage and dis engage would this cause a pressure build up problem to cause that line to blow (oh and it wasn't the line i rigged up wit was the one that had the good pressure rings...) any help would be greatly appreciated

 

Unless the 02 is way different from the 03+, the heater core hose you broke and replaced/repaired should have nothing to do with the AC line as the heater core runs coolant and the AC line runs refrigerant.

However, with the AC lines disconnect and the system to pressurized, was it ever sealed to prevent moisture or condensation from getting into the system?

 

no it wasnt the heater core line i replaced the heater core and cut one of the ac lines the low are pressure line and then rigged it with rubber hoses and clamps the high pressure line it what blew off could a bad compressure cause the pressure to build up that high to blow that line off