Details
Lower Group Head Mushroom O-Ring — EPDM 04075
This EPDM o-ring seals the lower mushroom valve inside the group head, the disc that opens to let hot water reach the puck on every shot. It's a wear item — EPDM handles the heat cycling well, but the ring still hardens and loses its seal over years of daily brewing.
SPECIFICATIONS
- O-ring 04075, EPDM, 3.53 mm thick, 18.64 mm ID
COMPATIBILITY
- Fits: Group heads using the lower mushroom valve with a 04075-size o-ring
INSTALLATION
Technician-level job — the group head has to be partially disassembled to access the lower mushroom, so this isn't a five-minute counter repair.
PRO TIPS
- A failing lower mushroom o-ring shows up as water dripping from the group between shots, not during brewing — if you're chasing a group head drip and the gasket and screen are fine, this o-ring is the next suspect.
Customer Reviews
Attention CA Residents: Prop 65 Warning
WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.