Ascaso coffee machine displays E5 and stops brewing; pump may run briefly then shut off.

Immediate actions:

• Remove the portafilter: If E5 appears during extraction, stop the machine and remove the portafilter. Check for overpacked or too-fine coffee puck.
• Backflush the group: Use a blind filter basket and Ascaso-approved backflush detergent (for models with 3-way valve). Run several backflush cycles to clean the group and solenoid valve.

Deeper checks (unplug before opening):

• Clean the shower screen and dispersion plate: Remove the group shower screen and dispersion plate. Soak them in detergent and scrub to remove coffee oils and fines.
• Inspect the 3-way solenoid valve: Access the valve and check for scale or debris in the inlet/outlet ports. Clean or replace the valve if it is stuck or blocked.
• Check OPV setting: On models with adjustable OPV, verify that brew pressure is within Ascaso specifications (typically around 9–10 bar) using a portafilter pressure gauge. Adjust if necessary.
• Review grind and dose: Ensure you are not grinding excessively fine or overdosing the basket, which can cause high pressure and trigger protection.

Warning: Do not adjust internal pressure components without proper tools and knowledge. Incorrect settings can damage the pump or boiler.