PRESSURE GOVERNOR
The pressure governor is used to control the flow of gas to the machine and to keep it at an even pressure. The governor is placed on the main gas line so the gas must pass through it before flowing to the machine. It is not necessary to have a pressure governor on each machine, for where there is more than one machine, a governor large enough to supply any amount may be secured.
The gas enters through a valve in the bottom of the governor and passes up into the supply chamber. From the supply chamber the gas flows out to the machine burner. The pressure in the supply chamber is regulated by an inverted cup float. The lower rim of the float is immersed in mercury, which causes the cup to float and also acts as a seal to prevent the gas escaping through the top of the governor. Weights are placed on top of the float to counterbalance the gas pressure. Fastened to the float is a rod which passes through the gas chamber. This rod connects to and operates the valve in the inlet opening. When the gas pressure is increased it raises the float by its pressure. When the float raises, it at the same time raises the valve in the intake, which decreases the opening through which the gas enters. Should the pressure in the main fall off, the float sinks deeper into the mercury, and the opening in the valve is opened, permitting a greater flow of gas. Thus the pressure in the gas chamber is held uniform, because the greater the pressure on the float, the smaller the opening for the gas to enter.
To regulate the pressure, place weights on the float until sufficient gas flows to the burners to give a good flame.