Electric water heater operating on low tariff - manual booster switch used outside tariff period

摘要

An electric water heater with its heating element switched by a control system, so that current is used during a low tariff period so that the water is maintained at given temperature level during that period, has a further manually operated switch which can be used after the tariff period so that the temperature can be maintained at a lower level outside the tariff period. The first temperature level is 80 deg. (+-) 10 deg.C. The heating element can operate at two levels of power and in an alternative arrangement, the higher power level may be employed during the period outside the tariff period. The heating element is switched off automatically by the control system when the set temperature is reached, and this setting may be fixed by a manual control.