Nuova simonelli expansion valve 18m 8 mm 98120001

What is an expansion valve and what is it for

The expansion valve is a safety component of the coffee machine's hydraulic circuit that regulates pressure in the water heating system. When the pressure in the boiler or heat exchanger exceeds the set limit, the valve opens the flow and diverts excess water back into the circuit or to the drain, protecting the other components from damage.

When the part stops doing its job

A worn or damaged valve shows up as unstable pressure during coffee preparation, fluctuating water temperature, or dripping and water leaks even outside of brewing. Sometimes you may hear hissing or unusual bubbling, as the valve fails to seal properly once operating pressure is reached.

When it's time for a replacement

A leaking or stuck expansion valve increases the risk of overloading the boiler and can lead to permanent damage to more important and more expensive parts of the coffee machine. Timely replacement keeps the pressure stable and protects the entire hydraulic system.

How to choose the right part

When choosing, it's important to check exact compatibility with your machine in the product's compatibility table, since valves differ in size and pressure setting depending on the specific model.

Compatible with

• APPIA (200610-)
• APPIA (200811-)
• APPIA (201103-)
• APPIA-1GR (200611-)
• APPIA-1GR (200812-)
• APPIA-1GR (201103-)
• APPIA-COMPACT (200802-)
• APPIA-COMPACT (201103-)