Specialty Coffee Industry Blog — Expansion Valve
What is an expansion valve? How do I set it?
The expansion valve on your espresso machine sets the peak pressure in your brew boiler. Most espresso machines are set to a peak pressure of 12-bar on bench (this is not to be confused with brew pressure which is set on the pump itself). However, in the process of preparing espresso machines for shipment, the expansion valve must be loosened. Therefore, the end user will often need to make small adjustments to the valve. If you notice that your expansion valve is set too high or low, please refer to the Operating Manual of your espresso machine for instructions on how...