70 adjacent the three way valve 72 gas line 70 is provided with a branch line 25 connecting the separator 58 with the gas sales line 76 downstream with respect to the three way valve 72 and upstream with respect to the check valve 78 the electrical control system 42 includes solenoids 90 92 and 94 connected in parallel with the pressure supply tank 40 by other tubing 96 a bank of batteries 98 includes necessary wiring connecting the electrical energy with the respective solenoid solenoid 90 is connected by an air line 100 with the valves 46 and 54 and solenoid 92 is connected by an air line 102 with the three way valve 72 while the solenoid 94 is connected by a line 104 with the air valves 62 69 82 and 74 for opening or closing these valves as presently explained in operation the compressor 66 is started by utilizing gas from the well head 18 via a bypass line 65 or a propane starter tank supply not shown the electrical control panel 42 controls all functions of the compressor as dictated by well head and discharge gas pressure in the well gas line 76 by responding to changes in preset parameters for operating the gas well 10 assuming the pressure in line 50 is not above the discharge set point as controlled by pressure switch 80 or the low pressure set point of pressure switch 81 the normally closed pneumatic valves 62 and 74 will open while the normally closed valves 69 and 82 will close this is accomplished by the pressure supplied by the gas well 10 through the line 44 into the air pressure supply tank 40 the pneumatic pressure supply tank 40 allows the.