The California Energy Commission “Appliance Efficiency Regulations” (CEC Title 20) require that, effective January 2008, all evaporator fan motors used in walk-in coolers and freezers less than 1 hp, and less than 460 V, must be electronically commutated (EC) motors. The regulation also prohibits the use of shaded-pole motors in both evaporators and condensers.
To comply with the mandate, Heatcraft Refrigeration Products LLC (HRP) has integrated new energy-efficient EC motors into its low-profile, low-velocity, and center-mount unit coolers. “Our EC fan motors are electronically commutated fan motors and represent the next generation in high-efficiency fan motors,” says Scott Seccuro, product engineer for the Stone Mountain, GA, U.S.–based refrigeration manufacturer. “Our EC fan motors range in efficiency from 60 to 90%, depending on the motor horsepower, versus 30–55% for traditional shaded-pole or PSC fan motors.”
Seccuro says that developing compliant products wasn’t an easy task. Due to the use of an electronic board in the motor, low temperatures and moisture are a major concern for EC motors in cooler/freezer applications. “The motor must perform down to –30°F (0°C) and be protected from moisture issues associated with condensation and defrost,” he says. Additionally, “the size of the motor must be maintained in order for it to fit in all installed and all new unit coolers.”
Besides adding them to its existing line of coolers, the manufacturer has decided to make the EC motors available as an InterLink aftermarket part. Because it is a drop-in replacement for existing shaded-pole and PSC motors, the company says contractors will benefit from the easy installation of this product while helping their customers to reduce energy costs without replacing the entire system.
Seccuro notes that the new motors are beneficial to all end-users, regardless of whether or not they are based in California. “The first reason is energy savings,” he says. “Energy savings can be as high as 60% versus a shaded-pole motor and 40% versus a PSC motor. The reduced fan motor watts reduce the heat load in the box, which reduces the load on the compressor. As a rule of thumb, for every 2-watt reduction in the fan motor, there is an additional 1 watt saved at the compressor.”
The motors also address environmental concerns. “Carbon dioxide is the major contributing gas to global warming, and coal-fired, electric-generating plants produce a majority of the carbon dioxide,” he says. “The EC fan motor saves energy and, reduces the amount of electricity needed, and, as a result, the corresponding carbon dioxide emitted into the atmosphere. The EC fan motor will reduce the amount of carbon dioxide emissions by as much as 7.8 tons over its lifespan.”