Valve Backflow Preventer

Image provided by Apollo Valves

Backflow preventers protect against reversed flow caused by backpressure or backsiphonage. Backsiphonage occurs when the supply pressure drops below atmospheric pressure, thus creating a vacuum. Backpressure occurs when the supply pressure drops below the residual pressure in the downstream piping. Either of these conditions can result in backflow. When cross-connections or potential cross-connections exist, backflow can result in pollution or contamination of the potable water supply.

A double-check valve assembly may be used under continuous pressure and protect against both backsiphonage and back-pressure conditions. It consists of two single check valves coupled within one body and furnished with test cocks and two tightly-closing gate valves.

Double-check valves have a test capability feature that gives this device a big advantage over the use of two independent check valves. Double-check valves can be readily tested to determine that both valves are functioning properly and are not fouled by debris. Each check valve is spring-loaded closed, and requires approximately 1 psig of pressure to open. Spring loading provides the ability to "bite" through small debris and still maintain the seal. Spring loading is a protection feature not prevalent in unloaded swing check valves.

Double checks are commonly used to protect against low-to-medium hazard installations, such as in food-processing steam kettles and in apartment projects.

Manufactures and Suppliers Participating in OPUS

Apollo Valves

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Aquatherm LP

Aquatherm is dedicated to providing the very best piping systems for anyone from engineers to...
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ASC Engineered Solutions

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F.W. Webb Company

F.W. Webb Company is a multi-faceted distributor of plumbing and heating, HVAC and controls,...
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Ferguson specializes in providing PVF, Plumbing, HVAC and Related Specialty Products and...
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Galloup Company

J.O. Galloup Company is a premier distributor of commercial and industrial piping products,...
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Hajoca Corporation

Founded in 1858, the Hajoca Corporation is the largest privately owned wholesale distributor of...
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Johnson Controls, Inc.

Johnson Controls, Inc. manufactures, installs, integrates, services and operates systems that...
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Jomar Valve

Founded in 1966 by former Navy Commander Joseph Martin, Jomar Valve set out to change the way...
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MIFAB is a manufacturer of seven different commercial plumbing product groups: 1) specification...
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MORSCO is a leading U.S. distributor of commercial and residential plumbing, HVAC, and PVF, with...
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NIBCO Inc. is a recognized industry leader of flow control solutions to the residential and...
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The Commonwealth Group

The Commonwealth Group is the industry’s newest, 100-percent member owned, $8.5...
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Watts Water Technologies

Watts Water Technologies  designs and manufactures valves and related fluid handling...
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WinWholesale, Inc. is comprised of over 525 wholesale distribution locations. Along with Noland...
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Zurn Industries, LLC

Zurn Industries markets and manufactures roof/floor drains, interceptors, cleanouts, water...
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