How to Replace a Sewage Pump Check Valve – Part 1

This project explains how to replace a sewage pump check valve for a basement bathroom with a silent check valve to prevent water hammer noise, pipe rattle and vibration when the pump cycles. The new unit is an A.Y. McDonald Mfg. Co. 2068S – Silent Compression Swing Check Valve – Socket Ball Valve Combo.

A.Y. McDonald Silent Compression Swing Check Valve 2068S 2067S

Sewage Check Valve Water Hammer

I installed a standard or “non-silent” check valve/shutoff ball valve combo unit when I finished the basement bathroom 3 years ago. The sewage check valve has about 12 feet of water head – meaning it holds back 12 feet of water in the vertical piping to where it empties into the main sewer line under the 1st floor joists. When the sewage ejection pump shuts off, that 12 foot column of water tries to flow backward and slams the check valve closed with significant force causing a loud thump and shakes/rattles the PVC sewer pipe. This is known as a “water hammer”.

The water hammer is an annoyance but since the basement bathroom is used only occasionally, I wasn’t motivated to pull the sewage pump (yuck!) and replace the check valve…. until now because I noticed the water hammer and pipe shaking was causing the solvent weld PVC joint to fail and leak. It’s taken the 3 years for the pipe joint to develop a leak, which for the time being seems to have gummed up and stop leaking. I’m sure I’ll have a big problem if it’s not repaired soon.

Sewage Check Valve: PVC Pipe Joint Leak Caused by Water Hammer

This next video illustrates the water hammer problem. I wrapped a red 12 gauge electrical wire around the 2 inch PVC sewage pipe to better illustrate the shaking.

Jumping ahead, the new A.Y. McDonald Silent Check Valve eliminates the water hammer and causes very little vibration as indicated by the white electrical wire. The valve closes at the 1 second mark in the video:

My application is a bit extreme as the A.Y. McDonald 2 inch silent check valves are rated for 2 to 10 feet of static water head over the check valve, where I have 12 feet of static head. I called A.Y. McDonald to ask if this would be a problem and the product engineer said the most common problem is not enough static head (less than 2 feet) which won’t reliably close the valve. With 12 feet of static water head the engineer said I should be OK because the valves are designed with a margin of safety. He explained my other option was to install two (2) check valves spaced such that the static water head was between 2 and 10 feet. I chose to keep it simple and install the single check valve.

A.Y. McDonald – Silent Compression Swing Check Valve

The A.Y. McDonald series 2068S Silent Compression Swing Check Valve and shutoff ball valve combo is dissembled here to show the individual parts. The check valve is available by itself as the series 2067S – Silent Compression Swing Check Valve if you already have or prefer to use a different ball valve.

A.Y. McDonald: Series 2068S Silent Compression Check Valve – Socket Ball Valve Combo

What I liked about the Silent Compression Check Valve are the black rubber gaskets and nuts that simply slide onto the 2 inch Schedule 40 PVC sewer pipe. The Compression fitting is a big advantage compared to a PVC Union with solvent weld pipe fittings in a sewage pump application because the compression fittings are easily removed leaving a bare pipe end. This means I can slide the sewage basin cover off the end of the sewage ejection pump stand pipe for maintenance. This point will become clear in later in this project when I have to saw off the solvent weld Union fittings on the old check valve.

Nested Flapper – Eliminates Water Hammer

What makes the A.Y. McDonald silent check valve different is the nested flapper in the top end that is key preventing the water hammer:

A.Y. McDonald 2068S / 2067S – Silent Compression Check Valve – Nested Flapper

The swing valve in the bottom of the unit provides a water tight seal to prevent backflow:

A.Y. McDonald 2068S / 2067S – Silent Compression Check Valve – Swing Valve

Here’s the A.Y. McDonald silent check and ball valve combo beside the old check valve. It’s slightly taller but that’s not a problem because PVC pipe is easy to cut and fit.

A.Y. McDonald 2068S Silent Check Valve compared to the Old Noisy Check Valve

This project is continued in How to Replace a Sewage Pump Check Valve – Part 2.

Thanks for reading,

Bob Jackson

Copyright © 2016   Reproduction strictly prohibited.

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10 Responses to How to Replace a Sewage Pump Check Valve – Part 1

  1. JJ January 31, 2013 at 12:43 pm #

    Bob, first off thanks for the basement bathroom series, gave me the confidence to do it on my own basement and it’s been fun and a great addition. The only thing that my wife doesn’t like about the new bathroom is that I put up a sign saying do not flush feminine products as I’ve read that they can jam up the sewage pump (I got 1/2hp Liberty model). I even asked the manufacturer and their response was no to do it, it may go through once or twice, but will jam eventually. Did you encounter this issue, how do you handle?

    • BobJackson January 31, 2013 at 7:01 pm #

      Yeah, people will (try) to flush all manner of foreign objects down the toilet.

      When the basement bathroom was opened for “business”, I held a family conference, explained how the system worked and said:

      “The toilet is not a trash can. The only thing that goes in the toilet is toilet paper, #1 and #2. Please inform your visitors of the rule. Because if I find a problem due to a foreign object, you’ll be helping me fix the blocked pump.”

      I think helping with pump repair made a lasting impression and there’s never been a problem.

  2. sam October 23, 2014 at 6:32 pm #

    Thanks for the information! Is there a way to unscrew the check valve on an already in-place system? Do they have to be cut off and replaced?

    I need to drain the tank with a shop-vac but can’t get access to the lid because of how the contract builders installed it. I think it has some foreign object in it as you described. I have searched all over the place and your article seems to be the closest match to the setup in the basement I am assisting with.

    Thanks again for the help and great info

    • Bob Jackson October 24, 2014 at 9:09 am #

      The combination swing check ball valve may have threaded connectors to remove the check valve cartridge for maintenance. See the cutaway diagram for the original unit that I replaced.

      You’ll need to examine your check valve to determine if there are threaded connectors. If so, it shouldn’t be necessary to cut out the unit. Hopefully the manufacturer’s name and part # will be on it then you can Google the specification sheet.

  3. Karl February 18, 2015 at 2:52 pm #

    Thanks for the information on the ejector pump check valve replacement–just what I need to get rid of the banging. My question is how would you connect the True Union Ball Valve to copper piping–I have PVC to the pump but overhead pipe is copper. Thanks again.

    • Bob Jackson February 18, 2015 at 8:53 pm #

      Use a Fernco Proflex Specialty Coupling to make the 2 inch PVC to copper pipe transition:

      “Designed for resistance to heavy earth loads and shear forces, and provides improved pipe alignment.

      Proflex allows you to make transition pipe connections that are resistant to shear forces, while creating a rigid, long-lasting pipe joint. From 1 ½” to 8″ – PROFLEX connects cast iron, plastic, steel, copper and tubular, drain waste and vent systems.”

      The plumbing connections would be:

      Sewage Pump – 2 in PVC Pipe – Union Ball Valve – 2 in PVC Pipe – Fernco Proflex Coupling – 2 in Copper Pipe

      The Fernco Proflex coupling is rated to a maximum 4.3 PSI, which equals 9.9 feet of water column. This means it’s suitable for use with a vertical sewage pipe not to exceed 9.9 feet tall above the level of the coupling.

      Take care to order the right Proflex Coupling for PVC to Copper as listed in Models table:

      Connecting Cast Iron, Plastic, or Steel to Copper
      Part No.: 3001-22
      Description: 2″ CI, PL. or ST. to 2″ Copper

      where CI = Cast Iron, PL. = Plastic and ST. = Steel.

      The Fernco Proflex 3001-22 is available at W.W. Grainger, Home Depot and

      Let me know if this solution works for you.


  4. Karl February 22, 2015 at 7:33 pm #

    Hi Bob,

    Thanks for your reply.
    I might not have been clear with my earlier question as I am thinking of doing as you did with installing the McDonald check valve AND the Ball Valve.

    Still thinking over this project and I have two questions.
    Is the Ball Valve needed or does it make replacing/servicing the check valve easier?
    Does the the Fernco Proflex Coupling also act as a reducer as the 2″ copper is smaller in dimension than the 2″ PVC?

    Thanks again,

    • Bob Jackson February 22, 2015 at 9:44 pm #

      > Is the Ball Valve needed or does it make replacing/servicing the
      > check valve easier?
      Exactly! The purpose of the ball valve is if you have to service the pump, the waste water in the riser pipe won’t leak or spill out – which would probably at the most worst moment.

      As we say in the sewer, here’s mud in your eye.” – Ed Norton

      > Does the the Fernco Proflex Coupling also act as a reducer as
      > the 2″ copper is smaller in dimension than the 2″ PVC?
      Proflex is designed to accommodate the small differences between plastic and copper pipe. If you check reader comments at the product link, the person mistakenly thought they were buying a direct connect size coupling.

      2 inch Schedule 40 PVC pipe has an actual outside diameter of 2.375 inches (2-3/8″) where 2 inch copper tubing has an outside diameter of 2.125 inches (2-1/8″).

      Swab some liquid dish soap inside the Proflex coupling for lubrication if you have trouble pressing it onto the pipes.


  5. Karl March 6, 2015 at 12:33 pm #

    Hi Bob,

    Did the install this past weekend. The MacDonald check valve and Fernco coupling were just the ticket–so far no more banging and the wife is happy!

    Thanks again,

    • Bob Jackson March 6, 2015 at 11:11 pm #

      That’s great! Good to know the Fernco Proflex coupling did the trick.

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