Tank, hoses and filter
Tank, hoses, filter and tank switch
Bezzera's manual says: if the machine is malfunctioning, do not try to repair it yourself; call technical assistance. Every BZ10 carries an anti-tamper seal that cannot survive opening the case, and Bezzera grants no warranty on a machine whose seal is removed or damaged (12 months from the invoice). Treat this as technician work.
There is no valve in the tank. It is a loose container with a suction tube and a return tube dropped in from the top; the suction tube carries a 200 micron filter (7374015). A switch under the tank support (G31 microswitch on a plate) works the orange lamp. A self-priming valve (7452516) sits in the pump circuit.
The owner's part is in cleaning the tank and filter: rinse the filter and keep the suction tube on the bottom. The switch and valve are inside.