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O-Rings & Seals
Round rubber seals used throughout the machine — group, valves, taps, fittings. Cheap to stock, instant fix for nine in ten leaks.
Category: Maintenance & Servicing
Rubber, silicone, or composite seals used throughout an espresso machine — on the pump, the boiler, the 3-way valve, the steam wand, the hot water tap, and many other places. Each one is sized and shaped for its specific application.
Why it matters — O-rings are consumables. They harden, compress, and lose elasticity over time. Most "mystery leaks" on an older machine trace to a failed o-ring somewhere in the system.
Good to know
- Material matters: EPDM o-rings handle hot water and steam well; standard nitrile rings fail under heat.
- Keep a basic o-ring kit on hand for any prosumer machine — most rebuilds are just replacing a handful of $1 seals.
Related: O-Rings & Seals