Cross Connection/Backflow Prevention
Many customers we have serviced have asked us numerous times what kind of part as seen in the picture is. The part is called a cross connection (CC) or back flow prevention (BFP) valve. In Canada and Alberta specifically the valve is seen on boiler, hydronic and irrigation systems.
The purpose of the valve is to prevent hydronic system fluids or irrigation system fluids from infiltrating the the domestic water supply to your home or water main service system. When system fluids of the the previously described systems enters the domestic water main, a harmful, dangerous and poisonous situation arises. The chemical used to treat boiler/hydronic and irrigation systems can cause some serious health realted issues and in extreme situations, a possible fatality.
A back flow or cross contamination situation arises when there is a pressure difference between the system water down flow of a BFP/CC valve and the water upstream of the two devices. When this situation occurs, water downstream of the CC/BFP can enter the water main.
As such, water main suppliers have been constantly upgrading and setting new standards to prevent cross contamination of the water main supply. The ultimate goal of enforcing the installation of back flow prevention/ cross contamination devices for the safety and protection of the public.
A third device used to prevent cross contamination or back flow is a device called a vacuum breaker. These are seen most commonly on hose bibs and commercial sinks.
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