The level-master control is applicable to any system that has been specifically designed for flooded operation. The valve is usually connected to feed into the surge drum above the liquid-level. It can feed into the liquid leg or coil header.
The insert bulb can be installed directly in the shell, surge drum, or liquid leg on new or existing installations. Existing float systems can be easily converted by installing the level-master control insert bulb in the float chamber.
The heater is provided with a two-wire neoprene-covered cord 2 ft in length. It runs through a moisture-proof grommet and a 1/2-in. male conduit connection affixed to the insert-bulb assembly (see Fig. 11-46).
The heater circuit must be interrupted when refrigeration is not required. Wire the heater in parallel with the holding coil of the compressor line starter or solenoid valve—not in series.
On some installations, the valve is isolated from the surge drum by a hand valve. A 2- to 3-lb pressure drop from the valve outlet to the bulb location is likely. For such installations, an externally equalized valve is recommended.