Descaling; Pid Controller; Cleaning The Stainless Steel - Quick MILL QM67 EVO Instruction Manual

Maintenance – Continued

Descaling

• Descaling is the process of running a descaling agent such as citric acid through the
machine to remove the accumulation of mineral deposits.
• If you are using softened water then it should not be necessary to descale the machine.
• Often times descaling can cause more problems than it solves. It can react to the minerals
and foam over ruining electrical components. If the solution is too strong it can cause the
chrome plating inside the group to flake off and get in the coffee or if it's too weak it can
dislodge minerals and cause a blockage. For liability reasons we strongly discourage
descaling and will not provide any instructions on the process.

PID Controller

The PID controller does not require any maintenance, but if the buttons have not been
•
used in a long time then the contacts inside the controller can become oxidized and the
buttons may no longer work.
To resolve this issue with the machine turned off, rapidly and repeatedly press the up and
•
down arrows over and over again. Do this for up to a minute and it should help clean off
the contacts and the buttons should start working again.

Cleaning The Stainless Steel

Specialty stainless steel cleaners can be used, but glass cleaner works well also. If there
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are dried up water stains then they can be cleaned with white vinegar.
After cleaning the machine using a dry lint free cloth to buff the machine will provide a
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nice mirror finish to the stainless steel.
QM67 Dual Boiler Espresso Machine
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