How to Replace a Backflow Valve

Pipes in the ground.
What You'll Need
Line wrenches
Hydraulic fittings
Metal drip pan
Pipe wrench

It is important to know how to fix a backflow valve so that you don’t need to hire a professional for what is otherwise a small and easy job. Also known as one-way check valves, backflow valves serve the purpose of preventing the backward flow of fluids in pipes.

Backflow prevention valves can be seen in two major categories: flapper valves and ball check valves. The importance of the backflow valve in home plumbing lies in regulating water supply through the pipes. Learning to replace a backflow valve is a fairly simple process that only involves some patience and the correct instructions.

Hazards of Backflow Valves Malfunctioning

If the backflow valves in the mains water supply system are not functioning correctly and there is a chemical plant or industry of some sort located in the vicinity, you run the risk of having your main water supply polluted. This is also true of situations where people have small workshops on their residential premises that are connected to the main supply.

In the case of gardening valves, there is always the risk of a backflow valve malfunctioning and causing fertilizers and other chemicals used in gardening to enter the main water supply of the house. Both these hazards are extremely detrimental to you and your family's health, so make sure your backflow valves are in top condition.

Common Reasons Why Backflow Valves Need Replacing

If a foreign body other than the water from your main water supply has entered the system, say excess street water following heavy rains, a flood, or there is some debris mixed with the water that is stronger than the flow of the mains system, it can cause the standard water flow to get distorted and the added pressure can cause the valve to burst, break or come off.

Siphoning happens when the level of pressure in the mains system suddenly decreases and this abrupt disparity in the general water levels leads to the creation of a vacuum. As a result, the water might start flowing backward up the pipe systems, causing the valves to malfunction.

How to Replace a Backflow Valve in the Garden

If you are replacing the backflow valve on your garden water sprinkler all you need to do is remove the existing faulty valve and put a new one in its place. The existing backflow valve will be fixed on the sprinkler hose using some kind of clipping or fastening. Use a wrench to undo this fastening and gently remove the defaulting backflow valve from its position on the sprinkler hose. Affix the new backflow hose valve using instructions from the manual that comes along with it. Make sure you clip the new valve back on safely. Once that’s done, use the fastenings to hold the valve onto its place and you’re good to go.