How to Change the Check Valve on a Sump Pump

Disconnect the sump pump from the power supply by unplugging the power cord.

Loosen the metal clamps holding the PVC pipes to the check valve using a screwdriver to loosen the clamp screws. Note that some check valves have pipes that slip inside the check valve without clamps, if this is the case proceed to Step 3. Otherwise skip to Step 4.

Saw off the PVC pipes running into the check valve. Use a hacksaw or PVC saw to saw a clean cut just above or below where the pipes run into the check valve.

Unscrew the screws holding the check valve in place and lift the valve off. Some discharged water may pour out.

Slip the tip of the discharge pipe into the new check valve's discharge outlet. Slip the tip of the intake pipe into the new check valve's intake outlet. If either pipe slides around and does not create a seal, proceed to Step 6, otherwise skip directly to Step 7.

Slide the pipe tips out of the check valve and connect a PVC coupler onto the tips. The coupler end should be slightly smaller than the discharge and intake outlets on the check valve. Use a PVC clamp to hold the coupler to the pipes.

Apply a generous amount of plumber PVC cement around where the pipes connect to the check valve and also where the coupler connects to the pipes. Replace and tighten the clamps if you removed them earlier.

Tighten the check-valve screws.

Plug the sump pump back in. Pour some water into the sump pit and wait for the pump to activate. Inspect the check valve for leaks and tighten screws/clamps as needed.