As a consortium representing the interests of the GeoExchange industry, the Geothermal Heat Pump Consortium (GHPC) appreciates the frequent attention paid to GeoExchange technology (a.k.a. geothermal heat pumps) inThe Air Conditioning, Heating and Refrigeration News.

However, we were disappointed by several inaccuracies in the article, “‘GeoExchange’ said to put money in the pockets of dealers, customers” (News, March 15, page 20). In the interest of accuracy and fairness, we’d like to make several points.

The reader is left with the impression that GHPC contributed much information to the story. However, GHPC was never contacted, and was not afforded the opportunity to comment or offer information for the article.

It is unclear just who is the author of the story. A byline should have clearly stated the company as the author. To have no byline suggests that The News wrote the story. That may very well be the case but it was clearly apparent that ECR Technologies played a large role in this article, since ECR is attributed at the end of the article.

ECR is a manufacturer of direct expansion GeoExchange technology, which employs copper tubing that directly circulates the refrigerant in the ground. This distinguishes it from “typical” GeoExchange technology, which employs a water-based fluid circulating through plastic (high-density polyethylene) pipes in the ground.

Water-based GeoExchange accounts for well over 95% of the total tonnage sold in the U.S., but one wouldn’t know that from the article, which is virtually a total endorsement of direct expansion (DX) technology as the only GeoExchange technology of note.

Strong DX bias leads to misleading statements like:

“Earlier systems circulated a water-antifreeze solution in an intermediate, closed plastic loop buried in the earth, then transferred that energy into the heat pump through an intermediate heat exchanger.”

This sentence implies that GeoExchange systems using plastic piping are antiquated and have been replaced with direct expansion, which use copper tubing. As noted above, the vast majority of the GeoExchange systems being installed today use plastic piping.

In fact, DX technology is not applicable in many large commercial and institutional buildings. The article implies otherwise. The picture of the drill rig on the cover of the issue and the caption incorrectly leads the leader to believe that the Webster County High School, near Upperglade, W.Va., a 500-ton installation, is a DX system. In fact, that school uses a water-based system.

ECR’s primary competitor in the direct expansion arena, American Geothermal DX (which was also attributed in the article but never consulted as to its content), does not pursue most large installations. According to Ron Castle, president of American Geothermal DX, direct expansion has great potential and is highly competitive in residential applications and in smaller commercial-institutional applications.

In the latter, direct expansion can be used if individual loop fields can serve individual units in individual zones (such as in one-story schools in which each room has its own dedicated direct expansion heat pump and loop field).

Of course, in such instances, one loses the diversity factor, Btu transfer due to simultaneous heating and cooling, synergy between loads (such as space cooling and water heating), and the resulting loop field downsizing benefits that are available when a project is served by one central loop field. Such a large field, however, cannot be a DX field.

The article makes the case that DX loop fields are much easier to install than water-based systems, since “no fusing or purging equipment is needed.” It is true that water-based systems require plastic fusing and must be properly charged with water and, if appropriate, antifreeze. However, the article doesn’t mention that DX loops require an involved installation process as well.

In DX loop fields, it is necessary to braze sections of the loop together with 15% silver solder and oxyacetylene, purge with nitrogen, pressure test with nitrogen or some other inert gas overnight (American Geothermal recommends the test be at 450 psi), pump down under vacuum, and then charge the system with refrigerant.

It is true that these processes are more familiar to most licensed mechanical contractors than water-based loop commissioning. In fact, many of these steps are required in the installation of split systems of any type. However, water-based loop commissioning is not very hard to learn. In any case, it is only fair to report that there certainly is substantial assembly required with direct expansion loop fields.

Throughout the article, numerous statements use the term “GeoExchange.” This is a service mark of the Geothermal Heat Pump Consortium, Inc., and is to be used to describe the technology in general terms for the entire industry, i.e., the entire pie. Having this statement intertwined in the story with comments from ECR Technologies leads the reader to believe that it refers to direct expansion systems only, i.e., a small slice of the pie.

The term “Direct GeoExchange,” which is used throughout the article, is a misnomer. It has no approved meaning and is not a permitted use of the Consortium’s service mark, “GeoExchange.”

Another misleading assertion in the article is the following:

“Surveys of GeoExchange systems owners consistently show that they rank their systems higher in comfort than do the owners of other heating and cooling technologies, and more than 95% of those surveyed stated they would recommend such systems to friends and family members, according to ECR Technologies.”

This statement suggests that the information is attributable to ECR Technologies. In fact, the information is not from surveys from ECR. It is from a survey conducted by electric utilities that questioned customers who had bought water-based GeoExchange systems, not DX systems.

While I applaud the attempt of this article to promote the increased use of GeoExchange systems, I am committed to making certain that all information about the technology is accurate, objective, and useful to The News’ readership.