Consumer Reports Posts Mixed Reviews About Tankless Water Heaters…
Heating water accounts for up to 30 percent of the average home's energy budget. Some makers of gas-fired tankless water heaters claim their products can cut your energy costs up to half over regular storage heaters. According to a recent Consumer Reports test, there are many positives & negatives to consider before investing in a tankless water heater.
Gas tankless water heaters, which use high-powered burners to quickly heat water as it runs through a heat exchanger, are 22 percent more energy efficient on average than the gas-fired storage-tank models. That translates into a savings of around $70 to $80 per year, based on 2008 national energy costs. Because they cost much more than storage water heaters, it can take up to 22 years to break even—longer than the 20-year life of many models. Moreover, an online Consumer Reports poll of 1,200 readers revealed wide variations in installation costs, energy savings and satisfaction.
With the help of an outside lab, Consumer Reports pitted Takagi and Noritz gas-fired tankless water heaters against three storage water heaters. Their tests simulated daily use of 76 to 78 gallons of hot water. That's the equivalent of taking three showers, washing one laundry load, running the dishwasher once (six cycles) and turning on the faucet nine times, for a total of 19 draws. The results of the Consumer Reports test is listed below:
Water Runs Hot & Cold:
Manufacturers of tankless water heaters are fond of touting their products' ability to provide an endless amount of hot water, however inconsistent water temperatures were a common complaint. When you turn on the faucet, tankless models feed in some cold water to gauge how big a temperature rise is needed. If there's cool water lingering in your pipes, you'll receive a momentary "cold-water sandwich" between the old and new hot water. And a tankless water heater's burner might not ignite when you try to get just a trickle of hot water for, say, shaving.
Nor do tankless water heaters deliver hot water instantaneously. It takes time to heat the water to the target temperature and just like storage water heaters, any cold water in the pipes needs to be pushed out. And tankless models' electric controls mean you'll also lose hot water during a power outage.
Up-Front Costs Are High:
The tankless water heaters tested by Consumer Reports cost $800 to $1,150, compared with $300 to $480 for the regular storage-tank types. Tankless models need electrical outlets for their fan and electronics, upgraded gas pipes, and a new ventilation system. That can bring average installation costs to $1,200, compared with $300 for storage-tank models.
Tankless Units Might Need More Care:
During long-term testing, an indicator on the tankless model warned of scale buildup. Consumer Reports paid $334 for special valves and a plumber to flush out the water heater with vinegar. Many industry pros recommend that tankless models be serviced once a year by a qualified technician. Calcium buildup can decrease efficiency, restrict water flow, and damage tankless models. Experts suggest installing a water softener if your water hardness is above 11 grains per gallon. Ignoring this advice can shorten your warranty.
Efficient Storage Models Are Pricey:
Consumer Reports also tested the $1,400 Vertex, a high-efficiency storage water heater by A.O. Smith. The manufacturer claims its installation costs are similar to a regular storage model but its high cost offsets much of the roughly $70 per year the Vertex will save you.