Bunn Dual SH BrewWISE, Technical Training Manual

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Bunn-O-Matic Corporation
15
Heating System
The heating system consists of:
Water tank •
Heating elements •
Triacs •
High-limit thermostats •
Temperature sensor •
The heating circuit maintains the water in the tank at a preset temperature this ensures that
the water is always ready for brewing.
Water for brewing is contained in an 8.4 gallon stainless steel tank. This tank contains 2
heating elements that are powered by the line voltage into the machine. Each heating ele-
ment is controlled by the control board through triacs mounted on the back of the brewer.
Each heating element circuit has a limit thermostat that will interrupt the circuit if the water
in the tank overheats.
The control board monitors the water in the tank by a temperature sensor that
is in contact with the water. This temperature sensor is a digital thermistor; the
control board reads the temperature as value of resistance. The temperature
sensor allows the control board to trigger the two heating element triacs when
the temperature drops below its programmed value and shut down the trigger
voltage when the water temperature reaches the programmed holding value.
Dispensing System
The dispensing system consists of:
Brew valve •
Bypass valve •
Sprayhead •
Funnel •
Funnel lock solenoids •
The dispensing system is what makes the brewer a coffee brewer. It dispenses the water onto the ground coffee to
create the product.
The BrewWISE
®
brewer is a gravity dump brewing system. During the brew cycle the brew and bypass valves open
allowing water to fl ow from the tank and out the product outlets. The control board opens and closes these valves ac-
cording to its programming based on the speci fi c recipe called for. The sprayhead, attached to the dispense solenoid,
controls the outlet fl ow rate of the water. The number and size of the holes determines the fl ow rate.
Bypass Valve Dispense Valve