Water in your house or any other building usually flows in one direction. However, sometimes, the flow of water changes, and potentially contaminated water mixes with potable water, resulting from backflow.
Backflow can be a severe health hazard as unidentified substances contaminate clean water, leading to the unchecked spread of water-borne diseases. Properly installed and maintained Backflow Prevention Assemblies can prevent such a situation from occurring.
Here, we give you a low-down on five of the most common backflow prevention assemblies you can find on plumbing systems.
Atmospheric vacuum breakers have an air inlet valve that remains closed when water flows in the right direction. When the flow reverses, air is brought in through the top of the device causing the float to open preventing back siphonage. These non-testable vacuum breakers are usually found on mop sinks and dishwashers in commercial buildings, along with some older irrigation systems.
A pressure vacuum breaker is a type of backflow prevention device, used to keep non-potable (or contaminated) water from entering the water supply. A PVB is similar to an atmospheric vacuum breaker (AVB), except that the PVB contains a spring-loaded poppet, check, inlet, and outlet shut off valves. This makes it acceptable for applications that are high hazard or where valves are downstream. However, the problem with PVB assemblies is that they don't have a defense mechanism against backpressure, so you should be wary of installing them in a system with chances of backpressure. Pressure vacuum breakers must be protected from freezing when installed outdoors.
These are a spill-proof version of a PVB, but they have an additional diaphragm seal to keep the water from spilling out of the air inlet while turning the assembly on. However, like PVBs, they too have no defense against backpressure.
DCVAs are standard backflow prevention devices that you can use for low hazard situations such as in fire sprinkler systems without chemicals. They are often installed in underground valve boxes or vaults near the water meters. They have an inlet and outlet shut-off valve and two spring-loaded checks in line with one another.
DCVAs provide protection against both backpressure and back siphonage. However, they cannot be used in high-hazard situations.
Also known as reduced pressure zone assembly, it is one of the most reliable and safe backflow preventers available in the market, but this safety comes at a higher price.
They are equipped with an inlet shut-off valve, two spring loaded checks, four test ports, and an outlet shut-off valve. They also have mechanically independent relief valve to maintain a lower pressure between the #1 and #2 check valves called the zone. The best part about RP backflow prevention assembly is that they can protect against all backflow situations including back siphonage and backpressure all in one go, making them an ideal option for high-hazard areas.
If yes, then you don't need to look any further. Backflow Testing & Repair LLC is your one-stop destination for all your backflow needs. We offer the best backflow testing service, repair, prevention, etc. You can reach out to us at (979) 215-1169 or fill our online form for any queries.
