I’m in the process of installing a salt-water chlorine generator (model DIG-60 from AutoPilot) for my swimming pool.  As part of this, I need to plumb the salt cell in downstream of my filter.  The cell is part of a big inline manifold which includes a 3lb spring check valve.  The valve’s purpose is to limit the water pressure going through the salt cell, theoretically extending the cell’s life.  Anyhow, as I was preparing to install the manifold, I dropped it (don’t ask) and the check valve broke away from one of its adjoining tees:

What to do here?  The whole manifold is solvent-welded together, and the tees are attached to proprietary unions.  At first glance there appeared to be no way to fix it other than ordering a replacement manifold, at a cost of over $100.  By contrast, a replacement check valve can be had online for $15-20.  So I decided to think outside the box a bit.  The check valve is made by Flo-Control and is commonly sold as an air check valve for spa blowers.  It has a 1½” socket and a 2″ spigot, meaning one can either attach a 1½” pipe “inside” it, or a 2″ pipe “around” it.  AutoPilot ships it with 2″ tees cemented to either side, which attach to the pool’s plumbing.  My pool has 1½” plumbing, so I would ordinarily need a reducer bushing to attach to the tees on the manifold.  When the manifold broke, the 1½” socket end of the valve was left stuck inside the tee.  Eventually, it occurred to me that if I cut the other tee away from the valve, I could flip the tees around and cement a new valve to the intact ends. The other ends, with the remains of the original valve, would then accommodate my 1½” plumbing without the need for reducer bushings.  It seemed like a great plan, so I pulled out my trusty miter saw and cut the intact tee away from the old valve, leaving me with 3 pieces:

I then went online to look for a replacement valve, and promptly ran into another problem.  It turns out that this particular valve is sold in a bunch of different spring weights:  .75, 5, 10, and 15 pounds, to name a few.  The version that ships with the AutoPilot has a 3lb spring.  And here’s the problem:  I wasn’t able to find the valve with a 3lb spring anywhere.  It’s not even listed on Flo-Control’s web site.  They’re apparently made special-order for AutoPilot.

Undeterred, I wondered if I could remove the spring from the broken valve and reuse it in a new valve. With the help of a couple of makeshift “spring removal” tools I fashioned out of copper wire, I was able to extract the spring. As a proof-of-concept, I then replaced the spring with the help of some needle-nose pliers.  Encouraged, I went ahead and ordered an identical valve with a .75lb spring.  I chose the model with the lightest spring I could find, figuring it’d be the easiest to get out without damaging the valve.  The valve arrived a few days later, and happily, it was identical to the original valve, other than having a different weight spring and not being broken.  The lighter-weight spring easily came out of the new valve, and with a little effort I was able to insert the 3lb spring.  Turns out direction matters when re-inserting the spring:  it initially wouldn’t seat properly, but when I flipped it around it went right in.  With that, I had a working, non-broken 3lb check valve.  I then cemented the two tees onto either end of the valve, completing the repair:

All that’s left to do is plumb it in and make sure it works.  Assuming it does, my little accident (dropping the manifold) cost me a lot less than I had feared.