Bunn ES.1A - Manual (Page 6)

BUNN Espress™ Model ES•1A™
4
Hot water rinse dispensing tube and steam dispensing tube
The ES•1A™ is equipped with a hot water rinse dispensing tube and a steam dispensing tube. They are
operated by moving the levers located at the bottom of the machine from to side-to-side; they can be placed
in a continuously open position if required. The outlet tubes can also be rotated.
Boiler
The boiler is made of copper plating, 1.5 mm thick; it operates under a pressure between 1.1 to 1.3 bar
(16-18.8 psi). This is measured by means of a pressure gauge with a scale from 0 to 2 bar (0-29 psi). The
safety valve assures that boiler pressure never exceeds the safety limits; it automatically discharges steam
when pressure inside the boiler exceeds 1.8 bar (26.1 psi). The water heating element is an electric resistance
unit controlled by a pressure switch. This switch automatically regulates the pressure of steam in the boiler.
The pressure switch will automatically shut off the heater when necessary.
Electrical pump
The electric pump incorporated in the machine is required to obtain optimum water pressure of 9 bar (130
psi) for espresso extraction. If water pressure from the tap exceeds 5 bar (73 psi), a pressure reducer should
be installed to avoid damaging the machine. If a pressure reducer is required, it should be installed in the water
inlet pipe just before the water conditioner or electric-pump.
HOT WATER RINSE
STEAM
FEATURES
P-157