Ahead of the Blower Curve Aprilaire Publishes Humidifier Performance Guidelines for ECM Motors

June 19, 2019

Beginning July 3, 2019, the DOE is requiring a maximum fan energy rating (FER) for furnace fans. The goal of this mandate is to reduce energy consumption as well as CO2 emissions. To comply with the new standards, furnace manufacturers are eliminating permanent split capacitor (PSC) motors and moving to electronically commutated motors (ECM). This will result in substantial energy savings and improved system performance.

Aprilaire concludes that the performance of all types of whole home humidifiers, bypass, power and steam will benefit from the shift to ECM technology in HVAC systems.

“This is great news for contractors as well as homeowners, and of course the environment, stated Damian Mannino, Product Manager at Aprilaire. “ECM’s have been in the marketplace for many years, and contractors already know the benefits they provide.”

In addition to energy savings and motor efficiencies, the shift to ECMs will also benefit the delivery of humidification. Aprilaire Humidification Engineer Nick Balazs explains, “With single and multi-stage ECM systems, as duct pressures change from things like loaded filters, zoning, closed registers and the like, the fan ramps up and down in order to maintain constant airflow and temperature.”

“As has always been the case, all 3 types of humidifiers; bypass, power and steam provide excellent performance on both PSC motors and ECMs,” Balazs continued, “and when the HVAC system is sized and maintained properly, they all tend to perform better with ECMs because airflow is consistent regardless of fluctuations in resistance. So naturally, with more consistent air flow comes better delivery of humidity”.

Balazs concluded, “The takeaway here is, when choosing which type of humidifier to install, there are four factors to consider; air flow, climate (which affects system run time), plenum temperature and size of home. With the exception of variable speed ECMs used on modulating furnaces, where we recommend steam or power evap, the type of motor is not a factor.”

Aprilaire provides detailed applications guidance at

About Aprilaire

Aprilaire is the number one trusted brand in the indoor air quality industry for more than 60 years. As a division of Research Products Corporation, the company designs and manufactures whole-home indoor air quality products – partnering with HVAC contractors, distributors and home builders to provide health, comfort, energy efficiency, and preservation of the home.