Valve

There we will explain the purpose of the use of valves on espresso machines listed on this category page.

Vacuum Valve

The vacuum valve is the latest type of valve used on coffee machines. This valve remains open during heating of the coffee machine boiler, so that the false air can escape. Once this "false" air has been relaised the valve is closed with the pressure of the boiler. This prevents that your pressure switch kicks in too early.

Expansion valve

This valve is used to release the pressure of the hydraulic system, when the pump is running. In some cases this is set at a fixed pressure, but in a lot of cases this valve can be adjusted.

Non Return valve

The name might already indicate what type of valve this is, a valve where water can only flow into one direction. You will find this for example before a heat exchanger tube, so that the heated water won't flow back to other parts in the machine

Safety valve

This might be one of the most crucial components in a espresso mahcine. The boiler safety valve. This is the last part in a espresso machine which can prevent a catastrophe. When your other safety devices such as a pressure switch and thermostat have failed, your heating element will keep heating, so the pressure will also increase. The only solution is to relief this pressure from the boiler, that is what the boiler safety valve does. Do replace this part every 2 year, recommended by the manufacturers.