Thanks TroopaDoopa ! I do have a rather high head preassure that is going up to about 300 psi which in turn is cutting out the compressor. I evacuated and recharged the sytem with the recommended 1.43 lbs or r134a but it didnt help. Does this sytem have an orifice or an expansion valve and, where is it located? I figure if I am going to replace the drier, I might as well replace the expansion valve too. Thanks, Cliff