AHRI Addresses Uncertainty in DOE Test Procedure for Modulating Condensing Residential Boilers

November 19, 2012
Francis Dietz, Vice President, Public Affairs

Immediately Implements Changes; Working with DOE on Permanent Fix

Arlington, VA — An internal review by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) recently revealed an aspect of the current Department of Energy (DOE) efficiency test procedure for residential furnaces and boilers that may result in an inaccurate AFUE measurement for two-stage or modulating condensing residential boilers. The problem in the test procedure is in the calculations used to determine the AFUE when selecting the option of skipping the heat-up and cool-down tests.

These ratings were based on the current DOE efficiency test procedure, and the error is due to an inconsistency in those procedures rather than a failure to properly conduct the DOE test. All the involved models are highly efficient and exceed the current federal minimum AFUE for these products, so there is no issue with their compliance with federal minimum efficiency standards.

“As soon as we discovered this test procedure inconsistency, we moved expeditiously not only to ensure accurate equipment ratings for consumers and in the AHRI Directory, but also to work with DOE officials to ensure the issue is corrected for all products,” said AHRI President & CEO Stephen Yurek. He said that AHRI has implemented the following actions:
  • Requiring all new model certifications and AHRI certification tests of all currently listed models for this subcategory of boilers to include heat-up and cool-down tests;
  • Requiring the manufacturers of all existing models in this subcategory of boilers that are listed in AHRI Directory of Certified Product Performance to immediately do one of the following: (1) drop the rating to 90%; (2) discontinue the model; or (3) provide test results which include the heat-up and cool-down tests that support a higher rating; and
  • Developing appropriate calculations to determine the correct AFUE for two-stage and modulating condensing boilers.

In a November 19 meeting, Yurek, AHRI General Counsel David Calabrese, and other AHRI staff briefed DOE officials about the issue and discussed appropriate steps to remedy the situation.

In the meeting, AHRI urged DOE officials to expeditiously notify those manufacturers that are not participants in AHRI’s certification program (Allied Engineering Company Div. of E-Z-Rect Manufacturing Ltd; Baxi Spa; Conematic Heating Systems Inc.; Hamilton Engineering; Navien America Inc.; Quietside; and Quincy Hydronic Technologies) of the issue so that the Department can take steps to ensure proper AFUE ratings for their affected products.

Access the AHRI Directory of Certified Product Performance ( for the most up-to-date information on the efficiency ratings for these products.

About AHRI
The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) is the trade association representing manufacturers of air conditioning, heating, commercial refrigeration, and water heating equipment. An internationally recognized advocate for the industry, AHRI develops standards for and certifies the performance of many of these products. AHRI’s 309 member companies manufacture quality, efficient, and innovative residential and commercial air conditioning, space heating, water heating, and commercial refrigeration equipment and components for sale in North America and around the world.