New U.S. Department of Energy (DOE) standards for residential high-efficiency furnace motors went into effect on July 3, 2019. Per DOE standards to conserve energy, electronically commutated motors (ECMs), or X13 motors, must be incorporated with most residential furnace fans and air handlers.
What is an ECM?
ECMs are motors that vary the capacity at which a furnace fan runs. They don’t have an on/off switch, meaning they can slowly ramp up or down as needed. This saves energy by allowing the furnace to operate at a partial load. Many homes have furnaces sized to meet maximum heating needs, but they often don’t need to operate at full capacity.
In contrast, permanent split capacitors (PSCs) cannot vary capacity, resulting in furnaces that are prone to short-cycling, which can reduce the equipment’s overall lifespan and efficiency.
New federal requirements
PSC motors have been the dominant option for the last decade, but in recent years ECMs have become more affordable. As a result, the DOE created a rule in 2014 to move the market to similar high-efficiency furnace motors.
As of July 3, 2019, manufacturers must follow the new standards. These standards necessitate that most residential furnaces/air handlers incorporate either ECMs or X13 motors. The DOE expects the change in motor standards to reduce furnace motor energy consumption by as much as 46 percent. The official ruling is available online.
Impacts on builders
The ruling impacts manufacturers but does not stipulate point-of-sale requirements for retailers or distributors. Builders should be aware that vendors will likely phase out their stock of non-compliant motors over the next several months. Energy Trust of Oregon is monitoring uptake of compliant motors within the EPS New Construction offering, and in the future, the code baseline will likely include ECMs to reflect this broader rule.
This is great news for consumers looking to buy new homes. More efficient furnaces will boost the energy efficiency of homes, leading to greater energy savings and comfort, along with a lower EPS.
Work with the EPS New Construction team and your rater/verifier to start incorporating ECMs into your designs and receive support with other energy-saving opportunities. For more information, contact the trade ally hotline at 1.877.283.0698.