Working out when to fill the boiler and then when to stop filling requires a little sensory perception on your machines behalf.

Before electronics became advanced and cheap enough, the operator had to use a manual filling valve and a level gauge to fill the boiler to the correct level, now we just let technology carry out this simple task.

To measure the water level inside the boiler we use an insulated stainless steel probe mounted on the top of the boiler.

The length of the probe can be mechanically adjusted to provide the optimum operating characteristics for the machine environment, depending on steam versus water usage. 

The water level is sensed by means of a low voltage electrical circuit that measures the resistance between the level probe and the body of the boiler.

Some machines will include an earth connection mounted on the level probe fitting, whilst cheaper machines will rely on a earth connection in other areas of the machine.