Setting Pump (Brew) Pressure - Quick MILL QM67 EVO Instruction Manual

Maintenance – Continued

Setting Pump (Brew) Pressure

• To set the pump pressure, install the backflush
disc into your portafilter and then lock it into the
group head.
• Remove the top cup warming tray to expose the
expansion valve adjustment screw shown on the
picture to the right.
• Raise the brew lever and then wait a few seconds
for the pressure to rise. After the pressure has
risen, use a flat blade screwdriver to turn the
expansion valve adjustment screw. Turning clockwise will increase the pressure, counter
clockwise to decrease the pressure.
• The recommended setting with the backflush disc is 9.5 - 10bar. When you make
espresso the pressure will be slightly less due to less resistance.
• If the machine is able to put out 9.5-10bars of pressure with the backflush disc, but when
you make espresso the pressure is 8 bars or less then that means the grind needs to be
adjusted finer which will create more resistance to raise the pressure. It is normal for the
grinder to drift a little over time and using different coffees or depending on the freshness
of the coffee may require a minor grind adjustment to stay in the preferred brew range.
• Tamping pressure can also affect brew pressure so be sure to tamp with the same 30lbs
of pressure each time. Tamping too lightly will cause the pressure to be low and the shot
will come out quicker. Tamping too hard and the pressure will be higher and the shot may
come out too slow or not at all.
QM67 Dual Boiler Espresso Machine
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