Expansion Valve & Pump Pressure Check (≤12 bar / ~9 bar brew)
🌐 EN
~20 min
Hard
Created on September 21, 2025
6 views
Compatible Machines
La Marzocco Linea Mini
Related Links
Routine Overview
This routine keeps the integrated brew group safe and consistent by confirming the expansion valve limit (never over 174psi (12.0bar)) and setting brew pressure near 131psi (9.0bar) under real extraction.
This is an AI-curated routine. Please share your experiences and suggestions in the comments!
Routine Steps
Progress
%{completed}/%{total} completed (%{percentage}%)
1. Watch the IBG gauge during warm-up
As the machine heats, the IBG pressure will rise and should approach but not exceed 174psi (12.0bar).
If it stops below or climbs above 174psi (12.0bar), adjustment is required.
If it stops below or climbs above 174psi (12.0bar), adjustment is required.
2. Adjust the expansion valve safely
Remove the drain box to access the hex-shaped brass valve (18 mm tool).
Using adequate protection (hot component), turn clockwise to increase or counter-clockwise to decrease, in small (≤¼-turn) increments.
Reinstall the drain box between checks and confirm the gauge behavior.
Using adequate protection (hot component), turn clockwise to increase or counter-clockwise to decrease, in small (≤¼-turn) increments.
Reinstall the drain box between checks and confirm the gauge behavior.
3. Set brew pump pressure to ~9 bar
Remove the top and lower trays, loosen the pump adjustment lock-nut, and adjust the screw.
Turn clockwise to increase, counter-clockwise to decrease.
Do this while the machine is brewing with coffee in the portafilter, then lock the nut and re-test.
Turn clockwise to increase, counter-clockwise to decrease.
Do this while the machine is brewing with coffee in the portafilter, then lock the nut and re-test.
The expansion valve can discharge very hot water (~93 °C). Use heat-proof gloves and keep the area clear.
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