Heat Waves: High-Efficiency Furnaces, Boilers & Heat Pumps

New federal energy-efficiency requirements are here for boilers and on the way for furnaces. The changes mean that the least expensive boilers will reduce heating bills slightly. But the changes also mean that residents of northern states must purchase a more expensive furnace that has a higher minimum energy efficiency than furnaces in southern states require.

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Although the latest energy-efficiency requirements for boilers, furnaces and heat pumps are designed to reduce the country’s overall energy consumption, you should take comfort in knowing that most consumers will realize slightly lower home-heating costs if they buy a new boiler in 2012 or buy a new furnace in 2013.

New Department of Energy requirements for gas and oil boilers increase the required minimum annual fuel utilization efficiency (AFUE) ratings for products that are made on or after Sept. 1, 2012. (AFUE measures how efficiently that a system converts fuel to heat.) Manufacturers also are required to incorporate on all boilers technologies that were used previously on only some models, but experts whom we interviewed say these changes won’t increase the price of boilers by much or at all.

But when DOE introduces requirements for gas and oil furnaces in May 2013, the benefits for consumers will be more complicated. The minimum level of efficiency that will be required for a furnace will be significantly higher for residents of the northern half of the United States than it will be for people who live in the warmer southern half of the country. That’s because furnaces must be more efficient in colder climates to achieve DOE’s goal to reduce energy use. But home-heating experts say northerners will pay more money upfront for the better-performing furnaces and wait longer to realize financial returns than southerners will.

But don’t worry if you are looking for a new heat pump. Regulations on those products won’t change until 2015, and many of today’s products already meet the 2015 standards.

BOILER POINTS. Minimum AFUE requirements for boilers vary by type—gas- or oil-powered, steam or hot-water producing—but all types face increases that range from 2 percentage points to 5 percentage points. For instance, gas-powered steam boilers are required to have a minimum AFUE rating of 80 percent after Sept. 1, 2012, which is up from 75 percent. Minimum AFUE ratings for gas-powered hot-water boilers will increase to 82 percent from 80 percent; they will increase to 84 percent from 80 percent for oil-powered hot-water boilers; and they will increase to 82 percent from 80 percent for oil-powered steam boilers.

Although the changes affect only boilers that have the lowest AFUE ratings, experts tell us that those modest figures should reduce annual heating costs by roughly 2 percent to 5 percent, which amounts to a savings of between $38 and $94 per year for the average household.

Other DOE requirements affect boilers that are at every price point. For instance, gas boilers that use a pilot flame (a small flame that burns constantly to keep older systems ready to fire) must convert to an electronic-ignition system, which adds a 2 percent increase to efficiency, experts tell us.

North vs. South

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But the largest energy-efficiency gains for boilers of every type come from mandated technologies that automatically monitor water temperature. These controls, which often are referred to as reset systems, manage water-temperature output to match only what’s required to adjust your home’s temperature to the desired level, rather than always heating the water to the maximum temperature. These technologies don’t show up in AFUE ratings, but experts tell us that they add 8 percent to overall boiler efficiency.

Neither electronic-ignition nor reset functions are new to boilers, so boilers that already have these features meet the new design requirements. Boilers that were made before Sept. 1, 2012, and that don’t meet the new requirements will be sold until dealer inventories are depleted, and we have no idea when that will happen.

We also are told that some contractors will continue to seek out and install systems that don’t have electronic-ignition and reset functions, because the contractors consider such systems to be easier to set up and maintain. Although you can request that your contractor install a model that has these features, the only way that you can determine whether a boiler was made before Sept. 1, 2012, is to cross-reference the boiler’s serial number with the manufacturer.

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