It has been my habit to use Christy's Red Hot Blue Glue to mend PVC pipe.
I am happy with the performance and the repairs turn out very well.
I also note, with great interest, that it is rated for potable water pipes (NSF pw-G-dwv-sw).
Recently, I constructed a long water conduit with schedule 40 potable water PVC pipe (NSF-61). The pipe sat, unused, for a month or so, and we used an air compressor to test it (ONLY TO 60 PSI, CALM DOWN …) and when we let out all the air, it smelled like an open can of PVC solvent. Very, very strong smell.
OK, no big deal.
So I filled the pipes with water and let it sit for a few days. Then we drained all of that water out. Then we filled them with water a second time and let it sit for a few days.
When we ran the spigots to drain this second flush of water, the water had a strong and distinct smell of PVC solvent. Not terrible, but strong enough to notice.
So my question is this:
On a regular basis plumbers and pump and well guys and other contractors will fix potable water systems with PVC solvent and put those pipes into almost immediate use for drinking water.
Why is this OK ? If I can dry it out fully and then double flush it (sitting for days each time) and still smell the solvent, that means there is solvent in the water and that means people are drinking it.
Why is this OK ? Why should I ignore and/or not care about this ?
Thanks.
Best Answer
Your different methods are causing you to notice the smell more than normal.
I'm making a few assumptions, but if you create an airtight PVC pipe, where did you expect the glue to off-gas? It's going to fill the inside of the pipe, especially if left for weeks. The air volume of the inside of the pipe is pretty small, so it's a high concentration. You probably shouldn't be breathing in the test pressure exhaust when you vent it.
Next you said you "flush" it for several days, but filling a pipe with water and letting it sit, then draining it, and doing that twice isn't a flush. Again I'm making assumptions, but that's what it sounds like you did. Run fill pressure water through the pipe for several minutes with it going to drain to actually flush it.
The volume of water sitting in a pipe is miniscule compared to running water.
I don't disagree, PVC glue and primers aren't good for you. We all just "waste" more water than you to rinse the pipe more, so we probably don't notice it.