Backflow Prevention Continued from page 38
system. This smaller, more compact size makes it possible to use smaller valve enclosures and freeze protection when needed, thus lowering the average installation cost. Historically, backflow preventers utilized a horizontal installation orientation. This caused the larger assemblies (4" – 10") to take up several running feet of installation space in a piping system. New approvals allow certain assemblies to flip that horizontal body into a vertical ori- entation, following the piping up a wall. This sounds sim- ple, but many assemblies arbitrarily taken from a horizon- tal to a vertical installation hydraulically will not prevent backflow. The demand for vertical orientation has caused manufacturers to address this feature in their designs. The cost of maintenance is becoming another factor that
With prices for bronze and copper so high, theft prevention is a consideration. This group demonstrates a few products to prevent or reduce theft.
reliable products. Once the products are approved, cost must be taken into consideration. Manufacturers have tried to provide fea- tures that reduce installation costs. Making these products lighter and more compact means that they require less physical space and equipment for installation in a piping
contractors are evaluating and manufacturers are address- ing. It is labor and material intensive to repair most older designs in the field. Field repair of newer designs is becoming far less labor and material intensive. Unfortunately, when business was good, some contrac- tors, not well trained in backflow preventer repair, would mistakenly tell their customers that it is cheaper to replace small assemblies (1/2" – 2"). As the economy has shifted, these same customers are questioning these statements and finding better educated contractors who can repair, rather than replace, installed assemblies when possible. For a couple more years, backflow preventers will con-
tain leaded bronze. For decades, bronze has been recycled through scrap dealers. The ever-increasing cost of copper (the major ingredient in bronze) has led to a proliferation of theft of installed backflow preventers and of other cop- per and bronze plumbing and electrical items. The most common theft has occurred on irrigation installations. Thieves remove the assemblies, and nobody realizes the irrigation is off until the sprinkler system is needed or until plant material dries up. Many new theft prevention devices, such as lockable enclosures, are coming to the market. In any industry, trends can be short or long. The trend
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for more economical manufacturing, installation and maintenance of backflow preventers will continue beyond good and bad economic times. The education of contrac- tors who install and repair backflow preventers will help them to be more efficient. In the past, manufacturers pro- duced products they could make easily and economically. New design features are forcing manufacturers to talk to their customers and to provide the product features they want to see. These are the trends for today. What the future holds is anybody’s guess. n
Circle 25 on Reader Reply Form on page 65 Page 40/Plumbing Engineer
Jim Purzycki is a wholesaler master parts distributor of backflow preven- tion assemblies with BAVCO. Purzycki belongs to many industry associations (fire, plumbing, irrigation and water works) and sits on national and region- al cross-connection control commit- tees. Jim teaches many backflow-relat- ed classes and seminars across the country.
March 2011
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