Both backflow preventer and check valve allows the water flow in one direction, hence, many assume that the two are for the same purpose. In reality, there are many fundamental differences between the two and they both have varied targets to perform respectively.

While both the devices come under the category of safety applications in different systems, the functions of check valves are more elaborate. Whether it is an irrigation check valve or backflow preventer, the choice between the two must be based upon the application, intended functions performed by them and other factors.

Keep reading till the end to learn the difference between these devices.

Application: Backflow Preventer vs Check Valve

The application of the two devices is one of the primary factors that differentiates them from one another. Backflow preventers are used in high-risk event applications. These have a fail-safe design that enables them to fully safeguard potable water.

On the contrary, check valves are used in low-risk scenarios and applied for efficiently halting water’s backward flow, however, they don't have the fail-safe components that are found in backflow preventers.

Backflow of water happens in any system due to potentially two prime reasons. One can be because of backpressure and the other is because of back siphoning. Backpressure happens when the downstream piping has a comparatively higher pressure than the supply piping. Elevated head pressure, pumps or heat expansions can all further make an influence to this scenario.

Alternatively, back siphoning happens when there is negative pressure for the supply piping. It is vital to have appropriate protective systems installed. This is when the question of backflow preventer or check valve application comes into play.

Why are the Backflow Preventer and Check Valve aren’t interchangeable?

Due to pressure changes, the waterflow can take a wrong direction within the pipes and this mainly causes backflow in systems. While the check valves are applied in order to ensure that the flow of water remains in one direction, the valves efficiently close the flow when the flow takes the wrong direction. This prevents the unwanted backflow within the system.

Check valves have been used in a variety of applications that includes protecting pumps and filters from the impact of backflow, preventing drainage in fire line sprinkler systems, offering pressure relief in pneumatic or liquid applications.

These valves have a pretty simple design that enables them to offer less human interactive functions and thus they can continue to run even when the power goes out. While the overall operations of check valves are impressive, they are primarily used in low-risk conditions especially where equipment damage is a prime concern.

Backflow preventers are used mainly in water supply links of cities or where potable and non-potable water interacts and other tough conditions. With the application of this device, the level of backflow protection reaches new heights.

Now, in case of backflow occurs, contaminants can severely impact the potable water supply line, therefore, raising a hazardous situation. With the backflow preventers application, operators can ensure that the water supply line remains uncontaminated as it makes sure that the water flows from the main to the pipe structure only.