Dissolve PVC Glue
Dissolve PVC Glue TIPS
- PVC glue is permanent if primer was used
- Heat can sometimes defeat the bond
- WATCH the PVC videos below
- Repair couplings are the answer
- opens in a new windowCLICK HERE to Get Tim's FREE & FUNNY Newsletter!
Roger Hull is working in a tight spot trying to dissolve some PVC glue. He's in Denham Springs, Louisiana. Here's what he asked me:
"I'm in a tight spot between floor joists. I'm trying to take apart some 4" PVC. Is there anything that will help dissolve the PVC cement?"
Here's my answer:
Roger, I've been a master plumber since 1980. PVC pipe and fittings was really starting to take off and become widespread about that time.
The chemistry of PVC primer and the glue or cement is such that it attempts to create both a chemical and mechanical bond between the two pieces of PVC. When you apply primer to the PVC surfaces, it softens the hard plastic at the surface.
As soon as you apply the PVC cement or glue, the softened molecules of the PVC then interlock with one another with the slightly melted PVC on the pipe and fitting.
It's very similar to how two pieces of steel join once they're melted and welded together. But be aware the contact zone where the pipe touches the fitting surface is not as strong as the actual pipe itself.
Watch these two videos to get an idea of how PVC works and why it's so hard to get the pipe and fittings apart once glued.
No Magic Liquid
I'm not aware of any liquid that will dissolve the cement that makes up a PVC joint. What's more, I can't even imagine how you'd get it into that tight space between the pipe and the fitting.
Not A Real Weld
You'll hear the term that the PVC will weld to each other, but don't confuse that with welding steel where the weld is often stronger than the individual pieces of steel.
In the case of PVC, the bond is pretty strong, but it's able to be defeated with heat, not a liquid. If you cut the piece out, you can sometimes get the male piece of pipe out of the female hub.
Repair Coupling Solution
If you can, it may just be easier to cut out the fitting(s), install new ones and use a repair coupling to make your final connection. The issue is as you increase pipe size up to 4 inches, you have VERY little working time to slide the repair coupling into position.
A repair coupling is one that doesn't have a center ridge inside and you can slide the entire coupling over a piece of pipe.
Heat makes it worse. Higher air temperatures decrease the working time.
I wish you the best of luck.
This column was updated and featured in the opens in a new windowMarch 15, 2015 AsktheBuilder Weekend Newsletter.