ERV Article Doesn't Reflect HVI's Views

It is true that this individual is the chair of this committee for HVI, but the position represented in the article on the use of energy recovery ventilators (ERVs) was a personal opinion. The article also quotes the chair of the HVI board of directors and another HVI member. We want to make it clear that the individuals quoted in the article were expressing individual opinions and do not represent a position of HVI.

The HVI Certified Product Directory, which can be found online at www.hvi.org, contains performance information on heat recovery ventilators (HRVs) and ERVs that have been tested for cold-weather performance. Currently, 37 ERVs have successfully completed cold-weather testing.

HVI, through its Certification and Verification programs, strives to provide the residential building industry and consumers with unbiased information and does not promote one technology over another.

We are concerned that HVI has been misrepresented and that readers of The NEWS have been misinformed in regards to the Product Certification Programs provided by HVI. HVI certifies the airflow, sound, and energy performance of a wide variety of residential ventilation products.

HVI is the leading North American trade association for manufacturers of residential ventilation products. Our mission is to serve consumers and members by advancing residential ventilation. Every year millions of HVI-certified residential ventilation products are sold throughout North America.

The Board of Directors, HVI
Wauconda, Ill.

Some Facts On ERVs and HRVs

In building his case that HRV is better than ERV in cold climates, the author employs the kind of "unsubstantiated claims, anecdotal evidence, and inaccuracies" he rails against in his introduction. He offers no data to support his remarks. Even the climate map includes application recommendations made by a manufacturer of HRV equipment, not the referenced sources. Not surprisingly, the only other "industry insiders" quoted are also employed by companies that market HRVs in the North.

In rebuttal, allow me to offer these facts.

FACT: Major manufacturers such as Venmar, Trane, Carrier, Sterling, RenewAire and others sell HVI-certified ERVs. The three HRV manufacturers quoted in the article also sell ERVs that are not currently HVI-certified.

FACT: ERV sales dominate HRV sales in the North American commercial products market with approximately an 85 percent market share. A residential breakdown is not available. However, a significant growth in acceptance can be inferred by the fact that five years ago only two manufacturers sold ERVs. Today, all HRV manufacturers also offer ERV models.

FACT: Energy recovery ventilation has been used successfully in homes and commercial applications in cold-weather locations from Minnesota to Maine for over 20 years - more than enough time to prove its value, and dispel concerns.

FACT: Like HRVs, ERVs moderate extremes in ventilation air temperature; ERVs also moderate extremes in humidity. In winter, this serves to control excessive indoor humidity without overdrying. When outdoor humidity levels are high, ERVs reduce building moisture loading and "stuffy and muggy" air conditions. Today, both warm-climate and cold-climate ERV advantages are recognized by most building scientists.

FACT: In winter, ERV humidity transfer reduces the humidity level of the exhaust airstream depressing the dew point (frost point) temperature and allowing the unit to operate without condensation or defrost systems under much more severe conditions than any HRV. This provides more ventilation capacity and higher energy performance in every climate zone no matter how severe. ERVs may require an active defrost based on the severity of the climate, the type of application, and the specific performance of the product. Every manufacturer must advise the proper use of its own equipment. There is not and cannot be a universal application map for all products.

FACT: HVI, "the premier, nonprofit association of home ventilating products manufacturers," has never advised contractors or end users to avoid ERVs in cold climates.

So, should ERVs be installed in Northern climates? For thousands of professional contractors and tens of thousands of homeowners - as well as many of the most well-respected HVAC manufacturers and distributors in the United States and Canada - the answer is an emphatic "Yes." The author should also have asked the question of them.

At the end of the day, ERV and HRV are competing technologies. In competition, it's expected that one brand amplify its own advantages and its competitor's disadvantages. We must rely on the market to pass judgment on those arguments. However, to portray a self-serving attack as an objective service to the industry only erodes the credibility of manufacturers and the industry association.

Douglas Steege
Vice President, Marketing and Sales
RenewAire LLC
Madison, Wis.

Spreading the Word on Matching Components

William G. Sutton
President
Air-Conditioning and Refrigeration Institute

Send correspondence via e-mail to letters@achrnews.com.

Publication date: 06/05/2006