hi every one
i got 4 ton split unit ac from general type heat and cool
with damaged compressor
so i replaced it with new one from some LRA and size
i checked compressor before installing so compressor worked properly
but when i started charging system i encountered this problem
if i charge the system with required amount of ***** by weight the compressor starting opening safety valves
but if charge system with little amount of ***** by weight the compressor and system work propely
i tried anothre types of ***** 22 and i made clean for the system and i changed the filter and expansion valves
i checked the electrical connection they are properly connected
can any one help me