
OPERATION (continued) | 
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  | WATER HEATER | |
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  | Water temperature is sensed by a thermobulb  | |
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  | inserted into the water tank. This temperature signal  | |
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  | is fed to the mechanical thermostat.  | |
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  | The setpoint temperature is adjustable. Heating  | |
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  | element is energized by the thermostat.  | |
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  | Excessive temperature will trip the   | |
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  | switch. The   | |
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  | brewer cools.  | |
Fig. 4  | Heat Control Diagram  | WATER FLOW | |
AUTOMATIC OPERATION | |||
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  | In COFFEE mode, pressing the BREW switch  | |
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  | causes the timer to energize the coffee brew  | |
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  | solenoid valve. This allows water from an external  | |
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  | water supply to flow into the water tank.  | |
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  | In TEA mode, pressing the BREW switch causes  | |
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  | the timer to energize the tea brew solenoid valve.  | |
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  | This allows water from an external water supply to  | |
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  | flow into the water tank. Additionally, the tea bypass  | |
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  | solenoid is energized, sending cold dilution water  | |
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  | from an external source to the dispenser.  | |
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  | Water flowing into the tank forces a like amount of  | |
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  | heated water out of the tank to perform the brew.  | |
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  | 
 | |
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  | If an external water source is unavailable, one  | |
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  | decanter of cold water may be poured into the  | |
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  | recommended for brewing tea.  | |
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  | AUTOMATIC OPERATION TIMER | |
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  | The length of time a brew or bypass solenoid is open  | |
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  | is controlled by the timer. The timer signal is routed  | |
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  | to either the coffee brew solenoid, or to the tea brew  | |
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  | and bypass solenoids, according to the position of  | |
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  | the mode switch.  | |
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  | HOT WATER FAUCET | |
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  | The faucet water coil is submerged in the hot water  | |
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  | tank and draws heat from the brew water. Water  | |
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  | going to the water coil is not controlled by either  | |
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  | brew solenoid valve.  | |
Fig. 5 Water Flow Diagram | Hot water is provided at the faucet, at supply water  | ||
pressure, any time the faucet   | |||
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  | 8  | |
M628 76201 Owners Manual 8781A Tea Brewer