Bradford-White Corp 900kW, 9kW TIME CLOCK Optional, PILOT LIGHTS Optional, ALARM BELL Optional

electrical input of the water heater in the summer months when ground water temperatures are warmer and full electrical input from the immersion heating elements is not required. The water heater may be restored to full input by moving the switches to the “ON” position.

TIME CLOCK (Optional)

FIG. 27 Time Clock

The water heater may be provided with an optional time clock. The time clock will allow the water heater to be turned on and off with a pre-set schedule. The time clock may be specified with a 24 hour scheduling period or with a 7 day scheduling period. By the adjustment of the setpoints on the time clock, the water heater may be turned off when hot water is not needed or in periods when the building may not be occupied. The time clock allows the water heater to automatically cycle on in advance of the time when hot water may be needed. This will insure that hot water is always available yet save energy when there are scheduled periods when there will be no requirement for hot water. This feature is especially useful for schools and building that are occupied on a fixed schedule. As an additional feature, time clocks may be furnished with a spring wound carry-over function to insure that a switching schedule is maintained in periods where there may be power interruptions. The time clock works by making and breaking the 120 VAC control circuit to the contactor coils to shut down operation of the heating elements in the desired time periods.

PILOT LIGHTS (Optional)

The water heater may be provided with optional pilot lights to provide an external indicator for each contactor or stage of heating elements that is energized. Each pilot light is wired in parallel with the 120 VAC control circuit feed to the contactor coil(s). The pilot will be turned on as the contactor coil(s) is energized by the temperature controls.

SHUNT TRIP DISCONNECT (Optional)

Shunt trip disconnect provides a power disconnect upon a control sensed malfunction via a circuit breaker installed in the main power supply to the water heater. The circuit breaker is shipped as a separate item that must be field installed. The water heater 120 VAC control circuit provides a feed to the circuit breaker that will shut down main power on either a low water level condition (if equipped) or high water temperature. Once the water heater is installed and all power is connected, the toggle switch that arms the shunt trip must be placed in the on position to provide the shunt trip function on the desired control sensed malfunction.

ALARM BELL (Optional)

FIG. 28 Alarm Bell

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