The spindle that really shuts off the steam
On the steam and water tap of the Premium Plus and the Evoluzione, this spindle transfers the rotation of the knob to the valve seat. It carries the gasket that holds back the steam when the tap is closed, and guides it cleanly onto its seat with every movement.
Here, wear shows up as a feeling in your wrist: the knob no longer turns silky smooth, it catches. Later a faint hiss appears that stays even after closing the tap – and tightening harder does not make it better but worse, because the gasket takes additional damage in the process.
When it is due
The tap hisses or drips when closed. The knob is stiff, jerky or has play. A freshly replaced gasket only lasts a few weeks. Grooves or wear marks are visible on the shaft. Or the machine is going in for an overhaul and the steam valve assembly is to be done completely at the same time.
At a glance
| Type |
Valve spindle for the steam and water tap |
| Installation location |
Steam and water valve assembly, behind the knob |
| Fits |
Rocket Premium Plus and Evoluzione |
| Scope of delivery |
One spindle. Gaskets, spring, knob and cap are separate items. |
| Part number |
R229905177 |
| Specification |
We have no documented dimensions or material for this number. |
| Brand |
Rocket |
| Installation |
Installation by a qualified technician recommended |
Who it is for
For anyone with a Premium Plus or Evoluzione whose steam tap no longer closes tightly – and for workshops bringing an older machine back up to standard without replacing the entire valve assembly.
Important for installation
The spindle sits in the steam path. Disconnect the machine from the mains, let it cool down completely and depressurise it before opening the valve assembly – a steam boiler stays under pressure longer than you think. We recommend installation by a qualified technician and deliberately do not provide step-by-step instructions here.
What goes with it
The matching gasket for the steam and water tap and the valve closure including gasket. As spindles for other model series, we carry the complete spindle for R58 and Bicocca and the spindle for the Appartamento. Everything else is under Rocket accessories and spare parts.
From our workshop in Bern and Zurich
Our routine, not a manufacturer specification: we treat the steam tap like a brass water tap, not like a screw. Turn it closed until it gently stops, then let go. Every extra bit of force goes into the gasket and eventually into the spindle. If you get into this habit, you will replace this part every few years instead of every few months. After any work on the valve assembly, we pull a cappuccino as a check – Very Nutty comes through most clearly in milk, Nutty Delight is our all-rounder, Cozy Chocolate the sweet cross-check. More under Coffee beans.
Returns excluded
Original spare parts are excluded from exchange and return. They are sourced specifically for each order and cannot be resold once they have been installed or test-fitted on a machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a line and we will check the fit together. Your rights in the case of defective goods remain unaffected.
Does the spindle fit my machine?
The part number is R229905177, and the item description names Premium Plus and Evoluzione. Rocket has changed the valve assembly over the years – send us the serial number and we will check the fit before you order.
Is a gasket included?
No. Only the spindle is supplied. Gasket, spring, knob and cap are separate items.
How does this spindle differ from the version for R58 and Bicocca?
They are two different part numbers for different model series. The item for R58 and Bicocca is also listed as a complete version; exactly how the two differ in construction is not documented to us.
Why does it keep hissing after the gasket has been replaced?
Because a worn spindle immediately damages the new gasket again. In this case, the spindle should be replaced as well.
Can I see the part in your showroom?
Yes. We are in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b. Bring the serial number of your machine and we will check the fit together at the counter.
Questions about fit? Write to us at [email protected]. Delivery across Switzerland and to Liechtenstein in 2-4 working days.
