Water Heater Manufacturing: From Ruud to ABB Robots

Water heater manufacturing is a quiet industry with a lot of steel in it. A typical tank is a rolled shell, domed ends, fittings, an anode and insulation, and almost all of it is joined by welding. This post follows the heater from the gas geyser of 1868 and Edwin Ruud's automatic storage tank of 1889 to today's robot welding cells. It also covers the heat pump heaters in the news this autumn, where ABB robots could fit in a plant, and what still holds factories back.

A gas-fired tank water heater newly installed in a basement. Photo: Tim Evanson / Wikimedia Commons (CC BY-SA 2.0)

From the 1868 geyser to Ruud's automatic tank

Hot water at the tap once meant heating it on the stove. In 1868 Benjamin Waddy Maughan, a British decorative painter, introduced the Geyser, an instantaneous gas heater named after the Icelandic hot spring. Cold water ran through pipes heated by a gas burner on the way to the bath. Its weakness was ventilation: with no proper flue, combustion gases mixed with room air, which made it hazardous. The Science Museum Group keeps a later gas geyser from Maughan's company, dated about 1900.

A modern wall-mounted instantaneous gas water heater with a flue pipe, a descendant of the Geyser. Photo: Wikimedia Commons (CC BY-SA 1.0)

Edwin Ruud, a Norwegian-born engineer working at the Fuel Gas and Manufacturing Company in Pittsburgh, changed the design. In 1889 he engineered an automatic storage tank gas water heater with a gas heater at the bottom and a temperature controlled gas valve, and patented it in 1890. The tank kept a store of hot water ready and the valve cut the gas when the water was hot, so nobody had to stand by it. Sources differ on whether the patent dates from 1889 or 1890.

A Ruud No. 3 instantaneous and automatic gas water heater in a basement. Photo: Jpmizell / Wikimedia Commons (CC BY-SA 3.0)

Ruud started his own company, Ruud Manufacturing, around 1897, and kept growing it into the early twentieth century. He received a gold medal for his automatic water heater at the 1904 St. Louis exposition. Rheem bought the water heater arm of Ruud Manufacturing in 1959 and kept the Ruud name as a division. The photograph, from an Electrolux factory in 1947, shows what hand welding on a production line looked like. Before robots, tank seams were welded by people with a torch or electrode, one tank at a time, and the quality of each joint depended on the welder's hand and eye on that day.

Workers welding parts by hand at an Electrolux factory in 1947. Photo: Tekniska museet / Wikimedia Commons (CC BY 2.0)

Robot welding cells and heat pump tanks

Water heater tanks look like an easy job for hard automation, which is a machine that moves a torch along one fixed path. The seams are simple and the product mix is small: the main variations are diameter and length. A 2024 article in The Fabricator describes a water heater maker that moved to robotic arc welding with laser vision seam trackers, and reports higher productivity, better quality and more flexibility. The article also says water heaters, gas tanks and pressure vessels are among the fastest growing segments in robotic arc welding.

An ABB arc welding robot with a positioner that turns a heavy part. Photo: Ana 2016 / Wikimedia Commons (CC BY-SA 4.0)

A vendor of laser seam trackers, Servo-Robot, claims that in some water heater tank plants the leak rate before repair, due to welding defects, fell below 0.5 percent, and that one operator can oversee several systems. Those are vendor claims, not audits. A separate integration guide notes that a robot repeats a path accurately, but quality still depends on how the part is located and how the torch meets the joint. Boiler makers such as Caldera and Viessmann use Cloos robots with positioners that rotate the boiler so both sides can be welded.

A tank-type electric water heater in a utility closet, the kind of product the welds hold together. Photo: Steven Pavlov / Wikimedia Commons (CC BY-SA 4.0)

ABB offers the same ingredients. The IRB 1520ID is an arc welding robot with its cables routed inside the arm, and ABB positioners turn heavy parts so the torch reaches every seam, as in the photograph. For short runs and repair work the GoFa CRB 15000 cobot has an arc welding package, which a worker teaches by guiding the torch by hand. I could not find a published ABB water heater customer, so this is a possibility, not a reference. Programs for such cells can be built and tested in RobotStudio before anything is installed.

Teaching a weld by hand with ABB's Easy Teach Device on the GoFa torch. Photo: ABB

What comes next for water heater manufacturing

Demand is moving toward heat pump water heaters. A. O. Smith's heat pump model earned the Good Housekeeping Seal in September 2026, Consumer Reports published its list of the best heat pump water heaters in October, and Rheem launched air-to-water heat pumps for multifamily buildings in September. A heat pump heater still has a steel tank, plus a compressor, coil and controls, so a plant has more kinds of assembly work to automate. An analyst note on A. O. Smith in September also pointed to replacement demand as a source of steady business, since tanks wear out and have to be swapped.

Two tankless gas water heaters mounted on an outside wall. Photo: Downtowngal / Wikimedia Commons (CC BY-SA 4.0)

Skills and cost are the open problems. A cobot cell can look cheap next to a dedicated welding machine, but fixtures, seam tracking and programming add up, and many shops have few people who can set them up. Safety rules around hot, heavy tanks need guarded cells. On 7 October 2026 A. O. Smith hosted 150 students at its McBee, South Carolina plant for Manufacturing Day, a sign that the industry is trying to recruit people for these jobs. Training material such as ABB RAPID instruction helps newcomers learn robot programming.

Guiding the GoFa torch to a pipe joint before the cobot repeats the weld. Photo: ABB

For a homeowner the future looks like a familiar tank, now often with a heat pump on top, or a tankless unit on the wall. The factory side matters because a tank holds hot water under pressure, and a bad weld is one place it can fail. The thermostat valve in the photograph does the same job as the temperature controlled gas valve in Ruud's 1889 design. A robot cell can repeat a seam thousands of times, while a person can then spend the time inspecting and fixing the rare bad one. Whether that happens depends on whether plants find the budget and the people to run it.

The thermostat and gas valve on a gas water heater tank. Photo: Infrogmation of New Orleans / Wikimedia Commons (CC BY-SA 4.0)

Innovation

AI solutions for effortless ABB robot control.

Automation

Robotics

ceojohntran@chatwithrobot.net

+84905311611

© 2025. All rights reserved.

qtran1215@gmail.com