Tankless water heaters—also called instantaneous, continuous flow, inline, flash, on-demand, or instant-on water heaters—are water heaters that instantly heat water as it flows through the device, and
The inside of a hydraulically operated two-stage tankless heater, heated by single-phase electric power. The copper tank contains heating elements with 7.2 kW maximum power.
Tankless gas electronic ignition water heaters. Gas water heaters have an exhaust vent or one to two exhaust pipes on the top, and still require electric power for electronics, sensing and ignition.
A three-phase, 21 kW, 400-volt tankless water heater in Europe, with new European color coding for three-phase power. There are also heaters that use several single-phase circuits instead
Tankless gas water heater with pilot light for ignition
Water heating is a heat transfer process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heatin
Tankless water heating
…Tankless water heaters—also called instantaneous, continuous flow, inline, flash, on-demand, or instant-on water heaters—are water heaters that instantly heat water as it flows through the device, and do not retain any water internally except for what is in the heat exchanger coil unless…
A small tank water heater
Electric-tank–type storage water heater (US)
Gas furnace (top) and storage water heater (bottom) (Germany)