How to Replace a Pool Spring Check Valve


  3 out of 5 stars on 9 ratings
(Click on a star to add your rating)

This picture shows a typical Spring Check Valve. If you have a pool Spring Check Valve installed in your pool circulation system and you notice water running backwards in your pool after you turn off your pool pump, you probably have a clogged Check Valve or one that has failed. With a clear Spring Check Valve, you can see if any debris is in the Check Valve mechanism that needs to be cleared out. See our guide on "How To Clear Debris From a Pool Spring Check Valve". Otherwise you can assume that the Check Valve has failed and needs to be changed. Most damaged Spring Check Valves cannot be repaired and must be replaced. This guide shows you have to replace a Spring Check Valve.

Step by Step


Step 1

UNION VS NON-UNION - Spring Check Valves come with unions and without unions. If your Spring Check Valve is installed without unions, you will have to cut it out every time you want to clean it or when you have to replace it. If you have an opaque Check Valve, you will have to cut it our just to look at it to see if it is clogged. For these reasons, a Spring Check Valve is usually installed with unions. This guide shows you have to replace a Spring Check Valve with unions. If your Spring Check Valve does not have unions, see our guide on "How To Replace a Pool Flapper Check Valve". The process for cutting out a non-union Check Valve is the same for all Check Valves.

Step 2

UNSCREW UNION COLLARS - To remove the Spring Check Valve you must first unscrew the union collars that hold the Valve to the piping.

Step 3

PULL OUT CHECK VALVE - With the collars off, the Check Valve will drop out of the piping.

Step 4

CHECK O-RINGS - Check the O-rings in each of the unions to make sure they are not cracked and that they fit snuggly in their grooves. Lubricate each of the O-rings with a silicon lubricant.

Step 5

INSERT NEW CHECK VALVE - Place the new Check Valve between the two unions. Make sure the FLOW arrow stamped into the side of the Check Valve is pointing in the direction of your pool's water flow. Note: you will have to buy the complete Spring Check Valve with Unions even though you will not be using the new Unions. Use the new O-rings.

Step 6

SCREW ON UNION COLLARS - Screw the Union Collars back onto the threads of the Check Valve. Hand tighten. You should not need to use a wrench if the O-rings are sound and in their grooves.

Step 7

INSPECT CHECK VALVE - Turn the pump back on and check for leaks around the Unions. If they drip slightly, you can tighten the Unions a little more. If that doesn't stop the leak, take the Unions apart agains and check the O-ring setting.

Step 8

MORE INFORMATION - For more information on Check Valves see our guide on "How To Select a Pool Check Valve - Overview".


(1 to 4 of 4)

 Posted: 9/25/2018 

Hello John - The valve used in this guide measures 5.05" long without the unions.

 Posted: 9/23/2018 

Can you tell me the length of this valve without the unions? Just the valve itself. thank you

InyoPools Product Specialist  Posted: 1/17/2017 

Big D - Unfortunately, we do not have that information. Try asking the pool builders in your area. They may have someone that worked on pools 20 years ago.

 Posted: 1/11/2017 

Our pool is 17 years old and I have noticed that when I turn off the pump the water in the spa flows back into the pool. Also when we turn on the spa the water also flows back into the pool very quickly. I'm told that I should "check" the check valve but there is no check valve visable. Someone mentioned that years ago builders placed then under ground. Q where should I start digging? Thanks Big D