La Marzocco GS/3 Installation Manual - page 8
English
6
La Marzocco, S.r.l. Firenze, Italia
Installation Guide
Unscrew the bleed screw (approximately 1/2 turn) to release all air from the coffee boiler
(using the included 5mm hex key wrench). When water leaks from under the screw head,
tighten the screw. Note: It might be necessary to activate the brewing process to force water
into the boiler. To do this, press the continuous key until water leaks from under the screw
head. Then tighten screw. Replace group cover removed in step #6.
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Next it will be necessary to check the expansion valve. As the coffee boiler heats to operating
temperature the pressure in the coffee boiler will rise. There is an expansion valve behind the
drain tray that allows some water to escape during this process to limit the maximum pressure
in the coffee boiler to 12 bar. Please monitor the coffee boiler pressure gauge during the initial
heating process. You should notice the gauge approach 12 bar and stop. If the pressure gauge
does not reach 12 bar or if the pressure gauge rises above 12 bar, then it will be necessary to
adjust the expansion valve. Please follow the next step to properly adjust the expansion valve.
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Steam Boiler
Pressure Gage
Coffee Boiler
Pressure Gage
Version 1.02