How to prepare for new water heating
Tank-style water heaters are undergoing high-efficiency makeovers to reduce energy usage.
Installing a propane-fueled, tank-style water heater used to be a one-man job. But with the introduction of more heavily insulated appliances, Melrose, Mass., plumber Petros Floros occasionally relies on a second installer for some extra muscle.
The practice could become commonplace by April 2015, when a U.S. Department of Energy (DOE) rule to increase the energy efficiency of all tank-style and tankless water heaters kicks in.
The new standards require every new water heater to have a higher energy factor (EF) a measure of its overall energy efficiency based on the ratio of how much hot water it produces to how much fuel it uses to heat the water. For a 40-gallon tank which DOE estimates is the most common size for a home using propane or natural gas the minimum EF will increase from .59 to .62 in 2015. For tanks larger than 55 gallons, however, the EF will balloon. A 60-gallon tank, for instance, will have a new minimum EF of .75, compared with .55 now.
To meet the 2015 standards, manufacturers of conventional storage water heaters are adding extra insulation to the tanks, rendering them, in most cases, two or more inches wider or taller. For heaters smaller than 55 gallons, heavier insulation alone could bring them into compliance with the 2015 mandate. But the only way to ratchet a 55-gallon-plus propane or natural gas water heater up to the new efficiency standards is to equip it with condensing technology, which could make the tank considerably larger, 50 or more pounds heavier and up to twice as expensive as a traditional model.
Manufacturers also are making the units more energy efficient by introducing newer flue baffling technologies, including flue dampers, and replacing the standing pilot light with an electronic ignition.
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DOE estimates that for a 40-gallon tank, the new standards will cut energy use by 3 percent. For a tank that holds 55 gallons or more, the savings could top 25 percent, as the condensing technology ensures that more of the energy the unit uses goes to heating water, so very little vents out of the house as waste through exhaust.
The higher efficiencies will shave homeowners' water heating bills, which account for 12 percent of the typical home's energy use, DOE estimates. When applied to the 9 million water heaters installed in American homes each year, the higher efficiency standards could save homeowners a collective $8.7 billion over 30 years, reduce household carbon dioxide emissions by an amount equal to the annual emissions of 30 million cars, and save enough energy to meet the needs of about 13 million U.S. homes for one year.
Plus, a condensing unit is so efficient that it produces more hot water and reheats much more quickly than a standard water heater after someone depletes the tank's reserves with a long, steamy shower.
Floros, owner of P Floros Plumbing & Heating, says some of his New England customers are ordering early models that already meet the 2015 standards.
To sell the higher-cost water heaters to homeowners, Floros explains the "green" benefits of the more-efficient units, noting that propane water heaters reduce greenhouse gas emissions significantly when compared with electric models.
"I go through the numbers with the customer," Floros says. "I explain that green costs [up front], but in the long run, what's it going to cost our children if we're not green now? Plus, there are [state and utility] rebates for these particular units."
Still, the environmentally friendly, higher-efficiency water heaters come with challenges beyond a steeper price tag. Floros says because basement ceilings in the neighborhoods where his customers live are typically only 6 feet tall, new, insulation-laden tanks just don't fit. In at least one home with plenty of floor space but a low ceiling, he replaced a large tank-type heater with two smaller units.
Indeed, the new standards could make "yank and replace" a practice of the past, at least for 55-gallon-plus tanks. Charles Smith, product manager for manufacturer Bradford White, notes that because a condensing unit produces water as a byproduct, it has to be located near a floor drain or have a condensate pump and line to expel the liquid to outside the home. In addition, new models with and without condensing technology feature energy-efficient motor blowers and electronic ignitions, which erase the need for a standing pilot light but require a nearby electrical outlet. Bradford White, for example, introduced 40- and 50-gallon atmospherically vented water heaters in June that have efficient blowers, electronic ignitions, additional insulation and a tightly restricted baffle system to comply with and even exceed the 2015 standards.
Large electric water tanks will require heat pump technology, which has its own installation challenges, to comply with the 2015 standards. Heat pump water heaters (HWPH) require installation in locations that remain in the 40- to 90-degree F range year-round, eliminating garage locations in many climates. They require at least 1,000 cubic feet of air space around the water heater and therefore cannot be placed in closets or other tight spaces. HPWHs are also taller than conventional storage tank units.
"Government requirements continue to move us to the higher-efficiency products. We need to be proactive and offer the high-efficiency units now...to reduce consumption of fossil fuels."
David Chisolm, marketing director for manufacturer A. O. Smith, advises plumbers and others who install water heaters to be aware of their options. "You don't have to do a like-for-like replacement," he says. "You've got more energy-efficient options now."
Capable and condensing
Indeed, some manufacturers have already introduced large, condensing water heaters for residential use. And some are offering smaller tanks with the same high-efficiency condensing technology, even though the new standards don't require it.
New 38- and 48-gallon residential condensing models by Rheem, for example, are 26 percent more efficient than most non-condensing units and meet the 2015 standards, the manufacturer says. They cost about $19 a month to operate. A. O. Smith has a 50-gallon power direct-vent water heater on the market, which it says offers 96 percent thermal efficiency; that is, 96 percent of the energy it uses goes to heat water, and just 4 percent exhausts as waste.
"Government requirements continue to move us to the higher-efficiency products," notes Brad Johnson, senior product manager of the water heating division at Rheem. "We need to be proactive and offer the high-efficiency units now...to reduce consumption of fossil fuels."
Floros advises plumbers and others who install water heaters to educate themselves about the new products and the 2015 standards. "A lot of things are changing in the industry," he notes, "and if you don't stay in the forefront of it, you're going to be left behind."
To learn more about efficient propane water heating, check out these Propane Energy Update articles: