Tankless electric water heater with staged heating element energization

摘要: A tankless electric water heater includes a housing provided with plurality of separate serially connected heating chambers defining flow path from cold inlet port to heated outlet port. Each chamber is immersion element and temperature sensor for producing signal indicative the in that chamber. The each independently controlled by control system responsive signals sensors produced an selector so energized only if sensed less than desired temperature. number elements proportional rate, necessary capability elements, thus eliminating problem overheating at low rates.