A knob that sits firmly in your hand again
On the Cellini and the Giotto, the steam and water knob is one of the few parts you actually operate every day. Open, hold, close – with every milk drink. Along the way it absorbs heat from the valve, catches milk splashes and is occasionally handled with wet hands. It’s normal that after a few years it no longer looks the way it did on day one.
It only becomes critical when it no longer grips properly. This replacement knob carries part number A430004284 and fits the Cellini and the Giotto.
When it’s time to replace it
The knob is due when its internal seat has widened and it slips on the valve spindle. When it shows cracks, especially around the spindle seat. When it gives way as you close it, so you need more force than before. And of course after a fall in which something broke off.
At a glance
| Type |
Knob, control part |
| Installation location |
on the outside of the machine, on the spindle of the steam and water valve |
| Fits |
Rocket Cellini and Giotto |
| Scope of delivery |
one knob |
| Part number |
A430004284 |
| Version |
Original spare part |
| Brand |
Rocket |
Who it’s for
For owners of a Cellini or Giotto with a worn or broken knob – and for anyone who wants both sides to look the same when only one needs replacing. Rocket has used different knob shapes over the production years. If you’re unsure, send us the serial number and we’ll check the fit before you order.
What goes with it
The matching clip, O-ring and caps for the knob are listed under Rocket Giotto and Cellini spare parts. You’ll find more control and valve parts under Rocket accessories and spare parts, and the full range under Original spare parts. For looking after your machine, machine and grinder cleaning is worth a look.
Our routine from Bern and Zurich – not a manufacturer’s specification, but what we pass on from the workshop: before fitting a new knob, we check whether the valve spindle turns easily without the knob. If it’s stiff, the cause lies in the valve, and the new knob will wear out just as quickly as the old one. When a knob is being replaced anyway, we replace the clip and the O-ring at the same time – they cost little and are easily damaged during removal. Then the test cappuccino: Nutty Delight, Cozy Chocolate or, for strong milk drinks, Very Nutty. All available under coffee beans.
No returns
Original spare parts are excluded from exchange and return. They are sourced specifically for each order and cannot be resold after installation or a test fit on the machine. So before ordering, please check the model, year of manufacture and serial number of your machine – or drop us a quick message and we’ll clarify the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
Is the cap included?
Just tell us what you need and we’ll confirm the scope of delivery before you order. We stock caps with and without logo separately.
Do I need two knobs?
The Cellini and Giotto each have one knob for steam and one for water. If you want both to look the same, order two.
Does it also fit a Mozzafiato or Appartamento?
Rocket uses different knobs on those. Tell us which machine you have and we’ll give you the right number.
How long does delivery take?
Across Switzerland and to Liechtenstein in 2-4 working days.
Can I see the part in your showroom?
Yes. We’re in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b. Bring your old knob along and we’ll compare them directly.
Questions about fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.