Homeowners warm to tankless heating's water, energy savings

European system finally adapted to North American market

David Bradley

Associated Press

April 23, 2004

Tankless water heaters are small, natural gas units wall-mounted either in or outside the home as pictured. CREDIT: David Bradley, Associated Press

North Americans love their hot water. Lots of it. And while tankless water heaters deliver unquenchable supplies of on-demand hot water, many homeowners are warming to other benefits of these appliances: big energy and water savings.

According to a water-heater expert, tankless versions can lop 30 to 50 per cent off water heating costs compared with traditional water heaters. On-demand heating doesn't waste water by allowing the flow to run until warm enough for use.

"A typical 40-gallon heater is like running your car all night in the garage until you drive it," says Peter LaRose of Nelson and Small, a northeastern U.S. distributor of top-rated Rinnai tankless heaters. "Why have a water heater running when you don't need it? A tankless system uses no energy until you turn on the faucet."

Tank systems guzzle energy nearly all day to maintain a preset temperature. As water cools, the system kicks on to reheat water. The cycle repeats day and night whether anyone is home or not.

And as many morning bathers who are last in line for a shower can attest, a tank water heater often can't keep up with high volume demand for showers, spa-like tubs and whirlpools. LaRose says only about 30 per cent of a tank is drawn off before water must be heated again. "It's an illogical way to heat water."

European homes use two or more tankless heaters to offset energy costs several times higher than in North America. But the demand for hot water -- and lots of it -- makes the U.S. market different.

Tankless heater maker Rinnai now markets a single unit better suited to American homes and American appetites for hot water.

The compact natural gas unit is wall mounted inside or outside a home. Sensors detect when a faucet is turned on, forcing water over a thin copper plate heated by 32 small burners. The unit is vented outside.

The compactness of the heater -- 18 inches wide by 27 inches high -- makes it a space saver. No mechanical room is necessary.

Homeowners use digital keypads to preset water temperatures to various rooms. Control pads are typically installed in laundry rooms, master baths or kitchens.

The keypads resolve safety issues, too.

Scalding water is a danger to small children or older adults. Tank systems heat water 130 F or higher, well above the 120 F comfort zone for most showers. Once set, tankless water cannot be heated above the preset limit.

Expect to pay $1,000 to $1,200 US for a Rinnai system, including installation. This compares with $200 for the cost of a tank and $300 to $500 for professional installation. Tankless systems are not a do-it-yourself project.

LaRose says beyond energy and water savings, homeowners will save on replacement costs. Tankless systems should last up to 20 years, nearly three to four times longer than tank systems.

"We think within 10 years, tankless systems will be the dominant source of hot water in North America," says LaRose. "As energy costs and water conservation become even bigger issues, homeowners will turn to tankless systems. It's the one responsible way to heat water for the home."

© The Vancouver Sun 2004