The same principle in a rotatable version – so the connection points to where there is space
As the machine cools down, the steam in the boiler contracts and a vacuum forms. The vacuum valve then opens and lets air in, so the machine does not suck water back into places where it does not belong. This valve does the same job as the fixed version – except that it can be rotated on its axis once installed.
That sounds like a minor detail, but in a tight housing it decides whether the outlet can be routed cleanly at all. Both versions carry the same part number L192.03 and the same 1/8 inch connection – the only thing that distinguishes them is the rotatable feature.
When it needs replacing
The valve drips or hisses constantly during operation. The usual sucking sound is missing when the machine cools down. The steam wand spits more than it used to after heating up. Or the valve can no longer be rotated because the seat is covered in limescale.
At a glance
| Type |
Vacuum valve |
| Installation position |
on the steam tap |
| Fits |
The documentation does not name a machine for this item. Send us the serial number and we will check the fit. |
| Scope of delivery |
one valve. Seals are not mentioned. |
| Part number |
L192.03 |
| Version |
1/8 inch connection, rotatable. We have no documentation on material and dimensions. |
| Installation |
Installation by a qualified technician recommended |
| Brand |
La Marzocco |
Important for installation
The valve sits at a point that carries steam. Work only on a machine that is switched off, disconnected from the mains, completely cooled down and depressurised. A vacuum valve is never readjusted, closed off, bypassed or blocked – it is a safety and functional component. By the way, being rotatable does not mean you turn it during operation; it refers to the alignment during installation. We deliberately do not give step-by-step instructions here.
Two items with the same number
Our documentation lists two vacuum valves for the steam tap, both with the number L192.03 and both 1/8 inch. The difference is only in the item name: this item is explicitly described as rotatable, the other is not. That is why we carry both and name the feature in the title instead of leaving one of them out. A rotatable valve can be turned on its axis once installed; a non-rotatable one sits rigidly. If in doubt, write to us – we will look at it with you before you order.
Who it is for
For workshops working on the steam fittings that need exactly the rotatable version because otherwise the outlet cannot be routed cleanly. And for anyone whose machine draws water back after cooling down.
What goes with it
The matching adapter is the G1/4 to G1/8 connector for the rotatable vacuum valve, A.5.154. Related parts are the rod B.2.013.01, the Teflon insert B.3.001 and the silicone O-ring 102. We carry the fixed version as a separate item, and the larger 1/4 inch valve as L190. You will find more parts under Original spare parts.
From our workshop
Before we order a vacuum valve, we turn the installed part in Bern and Zurich – carefully, on the cold machine. If it moves on its axis, it is the rotatable version; if it sits rock solid, it is the fixed one. This is our routine, not a manufacturer specification, but it settles the question more reliably than any parts list. And afterwards there is coffee: Nutty Delight, Cozy Chocolate or Very Nutty. More 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 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 check the fit together. Your rights in the event of defective goods remain unaffected.
Frequently asked questions
Why are there two valves with the number L192.03?
That is how it appears in our documentation. This item is explicitly described as rotatable, the other is not – that is the only documented difference. We carry both and say so openly instead of leaving one out.
What exactly does rotatable mean?
Once installed, the valve can be rotated on its axis so that the outlet can be aligned. It is not a control – it is not turned during operation.
Is there a matching connector?
Yes. Our documentation lists a G1/4 to G1/8 connector explicitly for the rotatable vacuum valve L192.03. We carry it as A.5.154.
Can I close off the valve if it drips?
No. A vacuum valve is never closed off, bypassed or blocked. If it drips, it is faulty and must be replaced.
Can I see the part in your shop?
Yes. In our showroom in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b, we are happy to show you both versions side by side.
Questions about the fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
