Power flow for all coffee espresso machines that have electric hookup will have an On/Off switch, water level control, steam pressure switch, Safety switch, High limit switch, and sometimes a critical temperature control. Gas fired systems use a sight glass with manual boiler filling. Gas heater is manually fired up and steam pressure monitoring by pressure guage. Modern systems eliminate the need to constantly monitor pressure, though remnants of those models persist in with pressure and sight water guages still being included. Guage s still adds a flair of credibility to a models with these old style devices.
1. Input utility power at 110-120VAC 15 AMPS or 200 to 240 VAC 30 AMPS, Both at Single (1) phase
2. On off power switch.
3. Boiler water level control. Checks water level and refills tank as needed.
4. With water filled. Water board passes control to steam pressure switch.
5. Boiler pressure is monitored by pressure switch. with no pressure it will be on to request heater elements to turn on.
6. heater contactor activates to supply AC voltage to element(s).
7. Steam pressure monitored for correct pressure setting. Usually at 1.2 BAR
8. Steam switch now directly controls the heating of boiler at this point.