March 2006 - Plumbing & HVAC

ADVERTISING FEATUREInexpensive efficiencyNear-condensing technology offers substantial benefitsfor building ownerA financial incentive to install high efficiencyboilers includes a category that may leave contractorsscratching their heads. The EfficientBoiler Program from Terasen Gas in B.C. offers$4,000 per boiler plus $2 per MBH plant input for‘near-condensing’ boilers in commercial/institutionalapplications.“A few years ago you would never hear of thatas a boiler technology,” remarked Doug Hannah,National Sales Manager for Flexible EutecticBoilers in Cambridge, Ont.As the name suggest, these boilers operate ina near-condensing mode. But most manufacturersof non-condensing equipment warn thattheir boilers should not be allowed to drop intothe condensing mode, which can damage theheat exchanger.Made in France and assembled to order byFlexible Eutectic Boilers in Canada, the DeDietrich 88 percent-plus efficiency boiler line fitssquarely into Terasen’s near-condensing category.In fact, with a remarkable 81ºF Delta-T – whenthe maximum for most boilers is 60ºF – the DeDietrich boiler can operate in and out of the condensingmode without risk of damage. Typicallya boiler condenses at about 118-120ºF-outlettemperature, explains Hannah. And yet the DeDietrich boiler can operate down to 105ºF.The efficient three-or-four-pass design is idealfor low NO x applications. “We have one schoolboard (customer) that has standardized on lowNO x boilers,” noted Hannah.As well, the boilers were recently approved tooperate at higher pressures in all provincesexcept Alberta: the GT300 is now rated at 81 psi,the GT400 at 91 psi and the GTE500 at 83 psi.The Canadian company takes its name fromthe unique material used in the heat exchangerfor every De Dietrich boiler. Eutectic cast ironis 30 percent more flexible than the grey castiron commonly used to create boiler sections.Developed in 1980 byDe Dietrich research and development engineers,the extremely fine-grained cast iron providesgreater structural integrity, very high corrosionresistance and the ability to withstandvery low water temperature returns.Hannah recommends water scheduling(indoor/outdoor reset) with continuous circulationto achieve maximum efficiency with a DeDietrich cast iron boiler. This permits higherefficiencies in spring and fall as a result oflower water temperatures required to meet theFlexible Eutectic Boilers, Canadian distributor of the De Dietrich boiler line, has moved to a newlocation in Cambridge, Ont. The expansion was needed to allow the company to stock more boilersand parts to keep up with a growing demand and ensure quick delivery to customers, reported DougHannah, National Sales Manager. Contact 519-650-0420 or 1-800-943-6275. More information isalso available on the company web site at www.dedietrich-canada.com.The Peel Regional School Board, west of Toronto, selected a De Deitrich near-condensing boilerfor this school heating system.building demands. During these periods theboilers can be operated in a condensing mode atvery high efficiency levels.Tests (conducted by Enbridge Gas) show thatfor every three degrees (F) that the water temperaturedrops, there will be a one percent fuelsavings. Combustion efficiency goes up substantiallywhen the boiler is operated at temperaturesunder 140ºF.Very little maintenance is required. Heatexchanger sections are joined with bi-sphericalpush nipples – there are no O-rings to rot out –and sealed with siliconed thermo cord to preventflue gas leakage. The unit is wrapped infour inches of high temperature insulation.All boilers have access doors that open to theleft or right, located front and rear. Maintenancetypically consists of periodic brushing and vacuuming.The life expectancy for a De Dietrichboiler is 30 years, even if the boiler is operatedin the condensing mode much of the time.One of the big appeals of a near-condensing boileris that it is substantially less expensive than afull condensing unit and yet can offer similarefficiencies for much of the heating season.Call Doug Hannah at (519) 650-0420 or goto www.dedietrich-canada.com for moreinformation.BOILERSwww.dedietrich-canada.comFlexible Eutectic Boilers1090 Fountain Street North, Unit 10Cambridge, Ontario N3E 1A3E-mail tom.turner@ezlink.on.caTel: 1 519 650-04201 800 943-6275Fax: 519 650-1709Circle Number 150 for More Information