The brewing group seal is subjected to extreme stresses: pressure, heat, and mechanical wear, so at some point it's time to replace it. But no problem, the seal can be replaced quickly, even without special tools.
Brewing group seal - function
The brewing group seal fulfills a crucial function in a portafilter espresso machine. It seals the connection between the portafilter and the brewing group, even under high pressure, and ensures that the water flows through the coffee and not past the outside of the portafilter. In environments with heat, pressure, and wear, the seal hardens over time and becomes leaky. Its durability depends heavily on use and careful cleaning.
Silicone or simple rubber - which group seal is better?
Silicone seals have long been standard at LaMarzocco, and they are available as replacement parts for many espresso machines. Silicone offers several advantages over standard rubber seals. First, they are much easier to insert, making replacement much easier for inexperienced users. The softer material also feels much more supple when clamping the portafilter. In terms of durability, at least in our experience, silicone performs very well. The seals harden less quickly and seal reliably even after many extractions. We recommend using a silicone seal for replacement, if available; the small additional cost is well worth it.
Which portafilter seal is installed in my machine?
Each brewing group has its own seal. Diameters and thicknesses often vary, so it's important to purchase the correct seal for your machine. Below is a list of common espresso machines and the corresponding seals. Simply enter the machine model in the search bar at the top right:
Change the brewing group seal yourself
Replacing the brewing group seal is easy, even for a novice. All you need is a flat-blade screwdriver and a little patience and sensitivity. Please make sure to protect your machine from scratches at the contact points between the brewing group and the tool. A cloth or a strip of sticky tape will help with this.
