La Marzocco linea mini Operating Manual - page 11

EN

11

7) Adjusting the expansion valve. 

The expansion valve is a component 

that limits the maximum pressure in 

the  Integrated  brew  group.  Heating  the 

integrated  brew  group  causes  the  water 

within to expand. Since the integrated 

brew  group  is  completely  saturated,  the 

expanding water causes an increase in 

pressure  within  the  boiler.  Without  a 

safety device the increase in pressure 

could  cause  a  rupture  in  the  boiler.

The pressure in the integrated brew group 

should never exceed 12 bar. The valve is 

hot, so, using adequate protection, rotate 

the expansion valve clockwise to increase 

pressure. To decrease pressure, rotate the 

expansion valve counter clockwise (see the 

following diagram).

Figure 2 - Expansion Valve Adjustment

Decrease 

pressure

Increase

pressure