Over the weekend, a neighbor tried to remove a water softener installed outside their house, and broke the lines. I helped them fix it, but one of the solvent welded joints I made failed. The main water line is PVC and the piping in the house is CPVC. We used a slip transition coupler to go from PVC to CPVC. We used Purple Primer and All Purpose Cement, both labeled for use with PVC and CPVC.
I normally wait 30 minutes after cementing these types of joints before applying water pressure, but the water was turned on only a few minutes later. The joint between the coupler and the CPVC separated.
I primed and cemented both surfaces again, and reassembled the joint. 45 minutes later, I turned on the water and the joint failed again.
My neighbor was able to locate a sharkbite transition adapter at a hardware store 30 minutes away, so we ended up fixing it with that.
So my questions are:
- Why did the coupler and CPVC pipe separate the first time? I thought that this type of cement sets within minutes.
- Why did the joint fail a second time?