When the steam tap gets stiff, the cause is usually the spindle
The spindle is the heart of the steam and water tap: it transfers the rotation from the knob to the valve seat and carries the gaskets that hold back the steam. Because it is moved several times for every milk foam and swings between room temperature and steam in the process, it is a classic wear part.
You hear and feel it before you see it. The knob no longer turns smoothly but jerks. At the end of its travel it takes more force than it used to. And at some point it keeps hissing quietly even though the tap is closed – a fine, steady sound that does not go away when you tighten it.
When it is due
The tap drips or hisses when closed. The knob can only be turned with force or has play. Scoring, notches or bright wear marks are visible on the spindle. The gaskets have been replaced, but the hissing has remained. Or the machine has many years and many thousands of milk drinks behind it and you want to renew the steam tap assembly completely once.
At a glance
| Type |
Valve spindle for the steam and water tap, complete version |
| Location |
Steam and water tap assembly, behind the knob |
| Fits |
Rocket R58 and Bicocca |
| Scope of delivery |
One spindle in the version designated as complete. We do not have a breakdown of exactly what it includes – we do not claim a parts list here. The knob and cap are separate items. |
| Part number |
R229905676 |
| Version |
Complete. Dimensions and material are not documented to us for this number. |
| Brand |
Rocket |
| Installation |
Installation by a specialist recommended |
Who it is for
For owners of an R58 or Bicocca whose steam tap no longer closes cleanly, and for service workshops that want to repair the tap assembly in one go instead of having to work on the same spot twice.
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 tap assembly. Steam remains under pressure for longer after switching off than most people expect. We recommend installation by a specialist and deliberately do not give step-by-step instructions here.
What goes with it
The gasket for the R58 steam and water tap, the valve cap including gasket, the complete steam wand for the R58 as well as the categories Rocket R58 and R60 spare parts and Rocket Bicocca spare parts.
From our workshop in Bern and Zurich
This is our routine, not a manufacturer specification: we never force the steam tap closed. A steam valve seals via the gasket, not via the force on the knob – anyone who turns it tighter because it hisses destroys exactly the part that is supposed to seal. If it hisses, we make a note and replace the spindle and gasket together at the next service. And after every milk drink we briefly purge before wiping the wand. Then a cappuccino as a check: Very Nutty holds up best in milk, Nutty Delight is our all-rounder and Cozy Chocolate the sweet counter-check. Everything else is under Coffee beans.
Returns excluded
Original spare parts are excluded from exchange and return. They are procured to order and cannot be resold after installation or a trial fitting on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a line and we will clarify the fit together. Your rights in the event of defective goods remain unaffected.
Does the spindle fit my R58?
The part number is R229905676 and, according to the item description, covers the R58 and Bicocca. Rocket has changed the tap assembly over the years – send us the serial number and we will check the fit before you order.
What does complete mean?
The item is listed by the manufacturer as a complete version. We do not have a parts list, so we do not claim a scope of delivery. The knob and its cap are separate items in any case.
Is it enough to replace just the gasket?
Often yes – but only as long as the spindle itself is smooth. If it has scoring, it will cut every new gasket open again, and the hissing will come back after a short time.
Can I do the replacement myself?
We recommend installation by a specialist. The tap assembly carries steam; it must be completely depressurised and cooled down before it is opened.
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 the fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
