Rocket ball plate for steam and water – the part that keeps the tap turning smoothly
A good steam tap turns softly. No jerking, no scraping, just an even resistance from open to closed. If the movement becomes stiff and you have to push hard at the end, this small plate inside is often the reason.
The ball plate sits in the mechanism of the steam and water tap and transfers the turning motion to the valve stem. It is a wear part: small, inexpensive and, for that very reason, easy to overlook during a service. Part number A229904333.
When it is due
It is due when the tap becomes stiff or scrapes as you turn it. When it keeps turning without any change in the steam jet. When play develops in the knob that was not there before. And when visible wear marks or a worn-out recess appear once the tap is opened.
At a glance
| Type |
Ball plate for the tap mechanism |
| Location |
Steam and water tap |
| Fits |
Rocket espresso machines with a matching tap version |
| Scope of delivery |
1 ball plate |
| Part number |
A229904333 |
| Version |
Single part, without spring, shaft and seals |
| Installation |
Installation by a professional recommended |
| Brand |
Rocket |
Important for installation
The ball plate sits inside the tap, which is connected to the steam boiler. Before working on it, the machine must be unplugged, depressurised and cooled down. We deliberately do not provide step-by-step instructions – anyone taking the tap apart is working on a pressurised assembly and needs the right tools and experience with the subsequent leak test.
Who it is for
For anyone whose steam tap no longer runs the way it did on day one. For technicians who replace all wear parts at once during a tap service. And for workshops that want to keep the part in the drawer, because it is needed more often than you might think.
What goes with it
The same job often calls for the spring for the steam and water tap and the O-ring for the steam and water tap. More parts for steam and hot water can be found under Rocket accessories and spare parts, and the full range in service and spare parts. You will find descaler for regular care in machine and grinder cleaning.
Workshop tip from Bern and Zurich
Our routine at the counter, not a manufacturer specification: when a steam tap becomes stiff, we replace the ball plate, spring and seal together. Changed individually, the tap often feels better only briefly, because the next tired part immediately stands out. Afterwards we froth a jug of milk to check how the valve behaves – for that we like Cozy Chocolate, for the espresso before it Nutty Delight and for strong cups Very Nutty. The full selection is in our coffee beans.
No returns
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 please check the model, year of manufacture and serial number of your machine before ordering – or drop us a line and we will check the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
Are the spring or seal included?
No. You receive the ball plate on its own. Spring, shaft and seals are separate spare parts – we carry the matching O-ring under A01335.
How can I tell that the ball plate is the problem?
Typical signs are a stiff or scraping tap and play in the knob. You can only be sure once the tap is opened.
Does the part fit my Rocket?
That depends on the tap version of your model. Send us the serial number and we will check the fit before you order.
Can I install it myself?
The tap is part of a pressurised assembly. We recommend installation by a professional.
Can I see the part in person?
Yes. In our showrooms in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b, it is available for comparison.
Questions about the fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
