238-47104-00A - Bradford White

SEQUENCE OF OPERATIONSome electric utility companies will offer discounts for using electricity during “Off Peak” Times of the day. The systemallows the use of an “Off Peak” meter, which interrupts power to the lower element during high power demand periods.Sequence of Operation- Double Element, Non-Simultaneous Operation, Single Phase, Off Peak.12Line voltage is applied across terminalsL1 & L3 of the upper thermostat. Line voltage fromoff peak meter is supplied to terminal L1 of lowerthermostat. ECO in the upper thermostat is closed,so there is voltage at terminal L4 of upperthermostat and to one side of the upper element.Tank is cold therefore both thermostatsare closed at terminal T2 (calling for heat). Thecircuit is complete through the upper thermostatonly, allowing current to flow through upperelement.FromOff PeakMeter1 2ECOClosedThermostat closedat terminal T23When upper thermostat is satisfied, it opens atterminal T2 interrupting current flow through upperelement, and closes at terminal T4 allowing voltageto pass to one side of the lower element. Thiscompletes the circuit through the lower thermostatand off peak meter allowing current flow throughlower element.Thermostat closedat terminal T24When the lower thermostat is satisfied, it opens atterminal T2 interrupting current flow through lowerelement. The system is now in stand-by modewaiting for the next call for heat5During peak power demand periods as determinedby the local utility, the off peak meter will interruptpower to terminal L1 of lower thermostat. Only thetop thermostat/element combination is allowed tooperate during this period.FromOff PeakMeter34 5Off PeakPower interruptedThermostat closedat terminal T4Thermostat closedat terminal T2Thermostat closedat terminal T2Thermostat openat terminal T2Page 1111