CV-10 Condensate Pump Accessory - Discharge Adapter/Check Valve

After recent furnace check and cleaning,mysteriously the condense pump valve was broken,I called for a repairman and was told the pump would have to be replaced at a cost of $225.00 (dollars) curiously I removed the valve and called the heating company back and requested the part,I was told the part would be next to impossible to find, I went online and browsed the brand name of the pump, and was referred to PexSupply.com: Problem solved..... Thank you PexSupply...

I bought this check valve/adapter for the Little Giant condensate pump for my daughters air condition system. I installed this check valve/adapter into the pump discharge line and hooked it up to the existing 3/8" tubing and put the pump into service. I tested the pump to ensure it worked by filling the pump reservoir up about three times. I noticed the flow in the discharge line started to back flow into the pump reservoir and the pump would cycle every few seconds. I removed the check/valve adapter and found that the seat and ball inside the check valve/adapter were both missing. I took the pump apart turned it upside down the ball and ball seat were in the bottom of the pump discharge line. I put the ball and seat assembly back into the fitting I noticed it was strictly an interference fit that kept the ball seat in the body of the adapter fitting. I put the adapter/check valve back into the pump and tried it again. After three or four cycles of the pump the check valve failed again as it did the first time. The only thing that could cause this is that when the pump turns off the 8 to 9 feet of head pressure in the vertical tubing falls down into the fitting and dislodges the ball check valve and ball out of the adapter body back into the pump discharge. This causes the pump to cycle excessively and I took it out of service. I went back on the internet and purchased a spring ball enclosed check valve that has barbed fittings on both ends and installed it into the pump discharge line. This check valve works as it should. The valve I bought with the pump to me was not designed to work with head pressure above it. The weight of the water when the pump cycles off causes the seat to be subjected to falling head pressure which causes the ball seat and check ball to be dislodged out of the adapter body. I would think this valve might be okay if the discharge line was a horizontal run instead of a vertical run. This valve could be used in a vertical line if the ball seat could be permanently attached to the adapter body by having threads or be sealed some how into the adapter body after assembly. The other thing I noticed is that this fitting comes with an "O" ring and the threads look straight and not tapered like a normal pipe fitting. There are fittings that have straight thread and use a "O" ring to make the seal into a grove that is machined into the fitting that the adapter screws into.