Operation of the block mounted inlet valve is exactly the same as the inline valve above.
The advantage of using a block for the inlet, is that other components like pressure relief valves and boiler drain connections can also be incorporated into the block assembly.
When the control circuit on the machine senses a low operating water level inside the boiler
, a voltage is applied to the electrical coil on the solenoid .
The applied voltage then causes the shuttle inside the valve body to retract, which then allows water to flow through the solenoid and into the boiler
Once the level in the boiler is at the correct set point, the voltage is removed and the shuttle returns to its closed state by the pressure from the spring mounted on the shuttle.