Thermo Scientific Barnstead G2100 Fully Automatic Controls for 1 and 2 GPH Classic Stills provide for unattended operation. Fully automatic controls include feed water and drain solenoid valves, manual valves, piping, and level monitor. Stops still when storage reservoir is full, starts still when the water level falls below a preset level. Drains still boiler at selected 4-hour intervals to reduce scale formation. The Controls include: control box, storage tank monitor, Inlet piping includes: solenoid valve, pressure gauge, manual regulating valve. 120 VAC.