Once upon a time in America, if you wanted hot water for your Saturday night bath you filled a vessel and popped it over an open fire. Consumer interest in having readily available hot water led to what was billed as the first “instant water heater” introduced in England in the 1870s.

Introduced in 2005, Rheem’s power vented, residential gas water heaters featuring the Guardian System for flammable vapor resistance was designed to meet Phase 2 of the American National Standards Institute Standard governing FVIR water heaters, effective Jan. 1, 2006. Photo courtesy of Rheem.

Norwegian immigrant Edwin Ruud, founder of the Ruud Manufacturing Co., is credited with invention of the automatic storage water heater in 1899. Many creative designs for water heating devices soon followed—made from copper, cast iron and assorted other materials and fired by wood, coal and even kerosene. 
   At one point early in the 20th century there were said to be more than 150 different water heater producers, all working without the silly bother of health and safety regulations. In 1936, A.O. Smith patented the glass-lined steel storage tank for water heaters—a true water heating milestone—adapting a process the Milwaukee company developed for the Wisconsin city’s local breweries. 
   Among notable safety features added over time were temperature and pressure relief valves as well as flammable vapor ignition resistance technology for gas heaters. The National Appliance Energy Conservation Act of 1987 addressed the standby loss, mandating increased insulation in water heating appliances. For the past two decades, regulation has focused on energy efficiency and reducing environmental impact.

A.O. Smith’s Vertex condensing tank water heaters offers up to 96 percent thermal efficiency. Shown is the Vertex Power Vent model. Photo courtesy of A.O. Smith.

Gas and electric tank-type heaters still fill a bill for a majority of households. Manufacturers say every water heater type is more efficient than its counterpart of even a decade ago, and efficiency ratings continue to rise, due to governmental mandate, environmental and energy use concerns and the awareness that standards will only get stricter. 
   The primary driver of product design and innovation has always been market demand, said Mark Taylor, director of commercial and technical sales for Bradford White in Ambler, Pa. 
   “The consumer and the marketplace have become more educated about the ‘greener’ technologies and higher efficiency; energy use cost savings are very critical at this point in time,” Taylor said. “We see consumers paying the long dollar to take advantage of the long savings.” Forums like the U.S. Green Building Council and its Leadership in Energy and Environmental Design building programs are pushing that technology, Taylor added: “Government entities are getting more involved in decreasing energy consumption, therefore increasing efficiencies.”
   From a consumer standpoint, an energy-saving water heating appliance is a good investment, said Alan Cape, manager of growth markets for Rheem’s Specialty Products Division in Atlanta. “When you add in the new federal stimulus plan’s energy saving tax credit incentives, it makes the payback period even shorter.” The new tax credit is 30 percent of the installed cost.

The Defender Safety System from Bradford White results in low NOX emissions and maintenance-free operation. Photo courtesy of Bradford White.

“The interest in and awareness of solar water heating was already there, but we think the tax incentives will be a catalyst,” said Jeff Mahoney, alternative energy manager, Rheem Specialty Products. “You also see utilities starting to drive consumer interest alternative water heating technologies,” he said.
   “We’re seeing renewed interest in alternative energy products, Cape said, noting the interest includes solar water heating and heat pump technology. “Sales of tankless gas heaters have become more popular over the past five years and we see that continuing as consumers become more comfortable with the product.” 
   The biggest leap in solar, Mahoney said, has not been in any significant new technology, but in best practices from installation and application of various solar technologies—making sure you have the right type of system for the right climate or usage.
   Rheem manufactures Energy Star-rated gas tank and tankless units, electric tank-type heaters and passive solar units. The company just launched its SolPak, an active solar product. SolPak is a pump system with solar collectors on the roof, a tank located remotely on the ground, and a pump and controller that forces the circulation. The advantages, Cape said, are that “it’s the more aesthetically pleasing of the options that are available and the ability to be installed in almost any climate, freezing or extremely hot.”

Better, more efficient performance and money savings are helping to drive the market for tankless water heaters, according to Takagi, manufacturer of units like the new TK-3-Pro for light commercial applications. Photo courtesy of Takagi.

Solar “is not going to go away,” Bradford White’s Taylor said. “With the advent of new incentives and the new technologies you can put solar applications in Northern climates and more hybrid systems are on the horizon, both combined energy sources and for combined water and space heating. As engineers become more familiar with the technology, hydro-heat systems should become even more accepted.”
   Consumers are seriously considering how they can save energy and have a smaller carbon footprint, agreed Aaron Siegel, vice president of sales and marketing for Eemax in Oxford, Conn., which manufactures electric tankless heaters from point-of use code-compliant hand washing products to high-capacity three-phase industrial units with flows up to 25 gallons per minute. “Now there is more awareness that a tankless water heater offers the convenience of not running out of hot water; but, a residual benefit is that it does save energy and has a low impact on the environment,” Siegel said. 
   “Electric tankless water heaters don’t have a venting requirement and so there are no greenhouse gases emitted using this type of product. They are typically easier to install because you don’t need a venting system for combustion air. With the efficiencies they offer, there is a lot of upside as far as benefit to the end user,” Siegel said. What attracts consumers to tankless is that it is essentially an unlimited source of hot water, so you can run consecutive showers without the downside of potentially running out of hot water, Siegel explained.

“Hybrid” water heaters like Grand Hall’s Eternal models, seek to combine the best features of tanked and tankless heaters into one sleek unit. Photo courtesy of grand Hall.

“Water heating typically accounts for 25 percent of the energy consumed by the average household; reducing energy use can have a significant impact on utility bills.” LEED initiatives and the U.S. Department of Energy’s Energy Star programs will draw more attention from consumers, builder and plumbers that there’s a better way to look at water heating systems, he added. Eemax electric tankless units are rated 99 percent efficient, certified by GAMA. Siegel noted that sizing is critical in tankless heating and plumbing professionals should access manufacturers’ technical support for every project.
   “The cool thing about changes in water heaters recently has been the whole energy efficiency push,” said David Chisolm, manager of brand marketing for the A.O. Smith Water Products Co., in Milwaukee. Chisholm said. A.O. Smith produces the gas and electric tank heaters, oil-fired boilers and commercial water heaters. Several years ago, the Department of Energy approached A.O. Smith to develop a high efficiency residential gas water heater. The result was the Vertex direct-vent condensing water heater with up to 96 percent efficiency. 
   In the Vertex heater, instead of venting out the middle of the tank, gases travel a 30-foot coil, offering more surface area and more time to transfer the heat from gas to the water, Chisholm explained. 
   “The net result is you can get a heck of a lot more hot water out of traditional-looking standard footprint product than you can out of even much larger units,” Chisolm said. “Not only is the Vertex more efficient, you can get continuous hot water, like a tankless model.” The product requires standard water and gas connections for retrofit and replacement and has side taps for secondary applications like space heating.
   “It was once tough to rationalize the expense of a product like this, but now you not only get the benefit of going green or being more conscious from an energy efficiency standpoint, but also get better performance and you get to put money in your pocket,” Chisholm said.
   Better, more efficient performance and money savings are the backbone of the whole “green” movement when it’s all said and done. And those factors are also playing a role in driving the market for tankless water heaters these days, according to Takagi south central regional sales manager Eric Muff.
   “Which is why Takagi provides a full product line of high efficiency tankless water heaters that can satisfy our customer’s needs. Quality, efficiency and safety are Takagi’s highest priorities. For example, we have a new T-K3-Pro model that recently received Energy Star rating for its high efficiency. The unit features a thermal efficiency rating of 84 percent for liquid propane and 82 percent for natural gas,” Muff said. “In total, we now have five tankless water heaters that are Energy Star rated. Takagi is also the first and only ones in the industry to use air-fuel ratio rods, a unique safety device that monitors the heaters to ensure that they are burning fuel efficiently, completely and safely.”

Wall-hung, condensing boilers like the Baxi Luna HT shown here, boast hyper-efficient operation and modulates between 112,000 and 32,000 BTU/hr. and puts out 3.9 GPM for domestic hot water production with an 80-degree temperature rise. Photo courtesy of Marathon International.

Bradford White also produces a complement of Energy Star-rated water heaters, including the Eco-Defender line of Low NOX and Energy Saver gas heaters, the High Efficiency electric heaters and condensing EF Series commercial gas models, and the EverHot tankless, Taylor said. 
   An example of new technology is the company’s Hydrojet system—a series of jet ports that create pulsation within the system to keep the bottom clear of debris and waterborne contaminants. It distributes water temperature more evenly within the tank so you get more hot water out of the heater—generally between 5- and 10 percent more if you look at the GAMA ratings for first-hour supply, Taylor explained.
   Grand Hall’s Eternal Hybrid water heater is said to offer key benefits of both tank and tankless heaters, said Paul Home, director of product development/marketing, Grand Hall in Garland, Texas.
   The hybrid pairs a heat exchange system with a four- to six-gallon storage tank half the height of a standard 50-gallon tank. The hybrid utilizes a turbo-charging fan atop the burner, so gas and air is compressed before being introduced into the combustion chamber. An advanced multi-pass heat exchanger drives heat downward and recycles it through stainless steel pipes for maximum efficiency. The small tank allows instant delivery and buffers against pressure drop.
   “You can turn on four or five fixtures for as long as you want and you don’t see any temperature or pressure drop. People associate this product with convenience; comfort and the luxury of endless hot water, and they are willing to pay for it. We are also seeing good acceptance in the light commercial area,” Home said. 
   Prime markets are California, Texas, Pennsylvania and New England especially in higher end retrofits and remodels. The company installed its Eternal hybrid in a 30-student house at Oberlin College in Ohio. One hybrid serves five showers, two sinks and two sets of washers. “Our unit replaced a 100-gallon tank and a boiler. It offers space savings and energy savings for them,” Home said.
   Both the West and the East coasts of the U.S. are strong markets for wall-hung boilers, long a staple in Europe, according Pat Kahnert, director of marketing and Western regional development for Mississauga, Ontario-headquartered Marathon International. Marathon has been the North American distributor for Italian-made Baxi boilers since the late 1990s.
   In the water heating category, Marathon offers two combination heating and domestic hot water boilers for residential applications—the Baxi Luna 3 Comfort near-condensing boiler with a 3.3 GPM output and 78-degree temperature rise and the Baxi Luna HT 380 wall-hung modulating condensing boiler, which modulates from 12,000 to 32,000 BTU and puts out 3.9 GPM for domestic hot water production with an 80-degree temperature rise. These models are a closed-loop system with two exchangers, Kahnert explained, the primary system that does the heating loop and a separate plate-to-plate separate loop for the domestic hot water. The boilers come fully pre-assembled and pre-tested from the factory. 
   The biggest applications are for multi-, and single-family dwellings. With the modulating range, a single unit can service homes from 600 to 4,000 square feet. Boilers can be set for specific heat load requirements.
   “The modulating range is critical to the efficiency of the unit. It really rewards green building environments where people are energy efficient and water efficient,” Kahnert said. “One key thing to keep in mind for the future is that the management of energy consumption is going to become mandatory, as it already is in Europe.”