HVACR NewsMagazine December 2017

S tate, National, Chapter News Tech News

and design, application work for numerous architects (primarily commercial projects) and design / build projects for our HVAC customers. Although this industry is very fluid and is constantly changing, there are numerous fundamentals in our industry which remain constant. Having held a number of schools over the years, one area which appears to cause some people problems in understanding its application and value…. is the measurement ‘ Inches of Water Column’. What-ever brand of product you represent, what-ever fan you install, you will notice in the cut (specification) sheet for that item a listing of the CFM values and the CFM performance based on “ inches of water column” (i.e. 1200 CFM @.5 in. WC). If you look at gas pressure be it natural gas or LP Gas, it is likewise rated in Inches of Water Column when it enters the appliance (i.e. furnace). Over the years, it has been my experience that many folks do not understand where this measurement in pressure (inches of water column) comes from and how important it is in our industry. As such I thought we might review this important unit of measurement. The pressure of air in sheet metal ducts, such as used in most AC and did significant

Inches of Water Column (Richard Clark, Legacy Partner)

Recently, Tom Hunt called asking if I would be interested in writing

an article (periodically) on industry related issues and topics for inclusion into his HVACR Newsletter. Having retired from the HVAC industry five years ago (after working in the industry 47 years) I initially told Tom, “I don’t think so” … I kind of enjoy retirement life as it currently exists, however after giving it some thought, I decided I would give it a try and write an article or two and see if I could bring anything to the industry and to the great, hard-working folks who comprise this industry. As many of you may be aware I was co-owner and co-founder of Environmental Equipment and Supply, who for26 years distributed numerous product lines through-out AR including “Rheem, Tempstar, Florida H.P, Bard, Ray-Tec. Carnes fans, et; et.” For much of our existence we had branches in Jonesboro and Memphis with the home office in North Little Rock. For many years I assisted our customers with service related issues