The compressor ports are marked 'D' and 'S', which I assume is 'discharge' and 'suction'. I have a conversion kit, from R12 to 134A, and it has adaptors for the shrader valves, marked 'H' and 'L', which I assume is 'high' and 'low'. Which is the high side, the discharge or the suction? (I know next to nada about A/C)
