Rocket Espresso Expansion Valve – Adjustable 10–14 Bar (RE-C229900911)

This is a genuine OEM replacement expansion valve (also known as an over-pressure valve or OPV) for Rocket Espresso machines. The expansion valve regulates the maximum brew pressure in the hydraulic circuit — when pressure exceeds the set point, the valve opens and diverts excess water back to the reservoir or drain. This is a critical component for maintaining consistent 9-bar extraction pressure and protecting the pump from over-pressure damage.

Technical Specifications

• Part number: RE-C229900911
• Pressure range: Adjustable 10–14 bar
• Hose end connection: ø 7mm
• Material: Brass CW510L (OT57)
• Lead content: Low lead

Compatible Rocket Espresso Machine Models

• Appartamento: 2017, from 2021-04, from 2023-04, TCA (from 2024-10)
• Bicocca: from 2024-07
• Giotto: 2009, Evoluzione 2 2017, Evoluzione V2 2013, Cronometro R (from 2019-08), Cronometro V (from 2019-08)
• Mozzafiato: Evoluzione R, Evoluzione V, Cronometro R (from 2019-08, from 2023-04), Cronometro V (from 2019-08, from 2023-04), Fast R (from 2025-01), Fast V (from 2025-01)
• Porta Via: from 2020-08
• R58: 2015, from 2018-02, from 2023-09
• R60V / R 60V: from 2018-02
• R8V: from 2017-11
• R Cinquantotto: from 2021-08, from 2024-10
• R Nine One: all variants including from 2020-09, from 2022-11

Check your machine’s model and production date on the serial plate (base or rear panel). If unsure, contact our technicians with your serial number before ordering.

When Should You Replace the Expansion Valve?

Replace this valve if your Rocket Espresso machine is showing any of the following: brew pressure consistently above or below 9 bar and not correctable by adjustment, water leaking from the OPV body or hose connection, the valve not returning to seat after pressure release, or a damaged or corroded valve body.

How to Adjust the Expansion Valve

The expansion valve is adjustable between 10 and 14 bar. To set your desired brew pressure, use a portafilter-mounted pressure gauge and adjust the valve’s set screw — clockwise to increase pressure, counter-clockwise to decrease. Most home baristas target 9 bar at the group head, which typically requires the OPV set slightly above this to account for line losses. If you are not confident making this adjustment, Bear Coffee Machine can calibrate it during a service.

Frequently Asked Questions

What is an expansion valve (OPV) and why does it matter? The over-pressure valve (OPV) limits the maximum pressure the pump can deliver to the group head. Setting it correctly is essential for dialling in 9-bar extraction — too high and you risk over-extraction and channelling; too low and shots will be weak and under-extracted.

Is this a genuine Rocket Espresso part? Yes — this is an OEM-specification valve using the original Rocket part number RE-C229900911, made from low-lead brass CW510L.

Can Bear Coffee Machine adjust or replace this valve for me? Yes — we offer in-house repair and servicing for Rocket Espresso machines. Contact us to arrange a booking.