Who invented the water heater?

Benjamin Waddy Maughan patented an instantaneous gas bath heater, the 'geyser,' in London in 1868, and Edwin Ruud, a Norwegian immigrant engineer in Pittsburgh, developed the automatic storage gas water heater in the 1890s, the direct ancestor of the modern tank.

Why do the British call water heaters geysers?

The name comes from Maughan's 1868 invention, marketed as the geyser after the Icelandic hot springs. The term stuck across much of the Commonwealth for gas bath heaters.

When did homes commonly get hot running water?

In the United States, automatic water heaters spread with gas and electric utility service, becoming common in new middle-class construction through the 1920s and 1930s and nearly universal after the Second World War.

Has the tank water heater changed much?

Remarkably little in concept since Ruud: a fuel source under or in a storage tank, a thermostat, a relief valve, and an anode. The refinements have been insulation, safety devices, and efficiency, not the architecture.

A Short History of Residential Water Heating

Page last reviewed: August 2026 · Reviewed by Harold R. Bennett, retired home inspector

The history of water heaters is short by the standards of household technology: for most of human history, hot water meant a fire, a vessel, and patience. The automatic appliance that made hot water a background utility is barely 130 years old, and its dominant form has changed surprisingly little in the last 70. This is the short version of how we got here.

Before the appliance: the kettle age

Into the late 19th century, bathing water was heated the way cooking water was: on the stove or over the hearth, hauled by the bucket. The first mechanization was the side-arm heater and its cousins, a coil or jacket plumbed to the kitchen range or a small coal burner, feeding a bare storage tank, often the cylindrical “range boiler” that stood beside stoves in period houses. These worked, slowly, and carried a real hazard: with no thermostat and no relief valve, an over-fired range boiler was a bomb, and exploding water tanks were a documented fact of 19th and early 20th century domestic life. The pressure relief valve this era eventually produced remains a legally required component today, tested annually per the T&P valve guide.

1868: the geyser

The first purpose-built domestic water heater is generally credited to Benjamin Waddy Maughan, whose 1868 London patent described a gas burner heating water flowing through wires and tubes on its way to the bath, no storage involved. He marketed it as the geyser. It was, in modern terms, a tankless unit, an irony given that tankless heating would spend the next century as the road not taken in North America. Maughan’s device vented indoors and lacked meaningful safety controls, characteristics that limited its reputation and occasionally its users.

The 1890s: Ruud and the automatic tank

The decisive figure was Edwin Ruud, a Norwegian-born engineer working in Pittsburgh, who in the 1890s developed and patented the automatic storage gas water heater: a gas burner under a tank, governed by a thermostat, requiring no attention at all. Ruud’s architecture, fuel below, storage above, control in between, is recognizably the machine in most American basements today. The company bearing his name manufactures water heaters still.

The automatic tank spread with the utilities it depended on. Gas service and, from the 1900s onward, electric resistance heating carried the appliance into middle-class construction through the 1920s and 1930s, and postwar building made it universal. Somewhere in this period, hot running water crossed the line from luxury to assumption, one of the quietest large upgrades in domestic living standards on record.

From the 1950s forward, the tank’s story is refinement rather than revolution: glass linings to slow corrosion, paired with the sacrificial anode rod that remains the tank’s secret lifespan mechanism; foam insulation replacing fiberglass and air; standardized T&P relief valves; flammable vapor ignition resistance after 2003; and steadily tightening federal efficiency standards that thickened insulation and improved burners. The failure mode, meanwhile, never changed: tanks still die of corrosion and sediment, on a timeline set by water chemistry and maintenance, per HOW LONG DO WATER HEATERS LAST.

The tankless return and the efficiency era

Instantaneous heating never disappeared; it matured abroad. Compact gas units became the norm in Japan and much of Europe, where space and fuel prices rewarded them, and modern electronically controlled tankless units re-entered the North American market in force in the 2000s, promising endless hot water and 20-year service lives in exchange for stricter maintenance, the modern ownership picture covered in HOW A TANKLESS WATER HEATER WORKS. The same era added condensing designs, heat pump water heaters that move heat rather than make it, and solar thermal systems, each pushing efficiency past what Ruud’s architecture alone could reach.

The bottom line

A London geyser in 1868, a Pittsburgh automatic tank in the 1890s, and then a long century of making the same good idea safer, tighter, and cheaper to run, with the tankless branch circling back home at the end. The machine changed less than almost anything else in the house; what changed was that nobody has to think about it, which was the invention all along.