The ring that keeps the drain under the machine dry
Under the drip tray sits the drain elbow, through which waste water is led out of the machine. It is screwed in and secured with a lock nut; the feed-through is sealed by this O-ring.
This spot is not under high pressure, but it is permanently in the wet zone, and it gets everything that comes out of the group: coffee residue, milk splashes, cleaning agents. Elastomers age faster in this mix than in plain water.
When it is due
A damp patch under the machine that does not come from the drain hose but forms around the elbow is the classic sign.
A second indication is a drain elbow that can be moved by hand. Then either the lock nut has come loose or the ring has lost so much material that the connection has play.
When moving or re-installing the machine, it is worth taking a look: once you have loosened the elbow, you should replace the ring rather than refit it.
At a glance
| Type |
O-ring, sealing ring |
| Installation location |
Drain elbow under the drip tray |
| Fits |
Rocket Boxer, RE A and R9 |
| Scope of delivery |
one O-ring, without elbow and without lock nut |
| Part number |
M449905463 |
| Version |
Elastomer |
| Installation |
Installation by a qualified technician recommended |
| Brand |
Rocket |
Important for installation
The drain elbow carries hot waste water. Before loosening it, switch off the machine, disconnect it from the power supply and let it cool down, and empty the drip tray beforehand. When reassembling, first align the elbow, then tighten the lock nut – doing it the other way round twists the freshly inserted ring.
Who it is for
For hospitality businesses with a Boxer, RE A or R9 where water collects under the machine.
For workshops that realign a drain or relocate the machine and renew the seal in the process.
The O-rings and sealing rings in the Rocket catalogue
Rocket uses a whole range of O-rings in the steam path, water path and boiler that look very similar from the outside. For most of them, the documentation gives neither the inner diameter nor the cross-section – they can only be reliably distinguished by their part number. That is why we list them individually, with the number in the title or in the table:
-
O-ring steam and water tap – A449904334
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O-ring for the steam and water tap cover – A449904672
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O-ring rotary knob steam and water, Cellini and Giotto – C400002786
-
O-ring water nozzle, Appartamento to Mozzafiato – C400003008
-
O-ring 3-way valve – M449907403
-
O-ring S2 valve – M449907143
-
O-ring 4250 silicone, R9 – M449905837
-
O-ring 3187 Viton, R9 – R499907384
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O-ring drain elbow, Boxer, RE A and R9 – M449905463
-
Copper sealing ring heat exchanger – C479900673
-
O-ring boiler top, Porta Via – A449906261
-
O-ring boiler bottom, Porta Via – A449906262
-
O-ring heating element, Porta Via – A449910266
-
O-ring 18 × 5 mm machine foot, R Cinquantotto – A449906954
If you measure your removed part and do not know the number, send us the model and serial number – we will check it against the exploded view.
What goes with it
The feed-through consists of three parts, all of which we stock individually: the elbow fitting for the water drain with part number M439905384, this O-ring with M449905463 and the lock nut for the drain elbow with M619905574.
The drain area also includes the drip tray drain plug with O-ring and the matching lock nut.
The machine category is Rocket Boxer spare parts, everything else is in Rocket accessories and spare parts.
What we do in Zurich: on commercial machines, we check the drain area once a quarter, when descaling is due anyway. A look under the drip tray takes two minutes and prevents exactly the kind of slowly spreading moisture you only notice once the surface underneath starts to swell. This is our routine, not a manufacturer requirement. For the test run we use Very Nutty, because under continuous operation it shows whether the drain keeps up.
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 before ordering, please check the model, year of manufacture and serial number of your machine – or drop us a short message and we will clarify the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
Are the elbow and lock nut included?
No. Only the O-ring is supplied. The elbow fitting and the lock nut are available as separate items.
Why is it still leaking despite a new ring?
In that case it is usually due to the lock nut, a damaged sealing surface or the drain hose itself leaking.
What are the ring's dimensions?
No dimensions are documented for this item. The number M449905463 is what counts.
Does it also fit the RE A and the R9?
Yes, the manufacturer lists the number for the Boxer, RE A and R9. In our shop a model tag is only assigned for the Boxer, because our category system does not have one for the RE A and R9.
Can I look at the part in your showroom?
Yes. We are in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b. Bring your removed part along, we will compare it with the replacement on site and you only take home what really fits.
Questions about the fit or the serial number of your machine? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
