How to figure out confusing plumbing and water flow directions
Pipes hidden under spray foam and non-standard DIY modifications make it nearly impossible to trace water lines or verify the correct arrangement of valves and pressure tanks. Without a clear path, homeowners cannot determine how water flows or whether components like shut-off levers and traps are set up properly.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Asking online forums for identification
- 2wrapping pipes with insulation
- 3trying to trace pipe paths through crawl spaces
- 4Having a plumber inspect and confirm proper venting
- 5Backwashing the unit to inspect the internal media
- 6Cutting out and lowering the tee to create enough room for the saddle
- 7Calling a plumber
- 8pushing the pipe further in with extreme force
- 9cutting the white pipe down with a hacksaw
- 10Asking for peer review on online forums before gluing
- 11Using slip joints instead of glue fittings for easier servicing
- 12Reaching out to the city supervisor directly
- 13Planning to use a male insert fitting with expansion sleeve and brass NSF parts
- 14Adding a union to the riser to allow lifting the RPZ off for maintenance
- 15Searching through previous forum threads with similar setups
- 16Relying on feedback and corrections from online communities
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“Before I make my final cuts and glue everything, does this look acceptable? First time ever doing plumbing work. Open to all suggestions!”source ↗
“now I can’t connect two pipes because they are not close enough to tighten together.”source ↗
“Thanks for popping in and telling me im wrong but refusing to be helpful!”source ↗
“Would the water flow on this system be from right to left?”source ↗
“Does the red lever shut off water "after" the pressure tank receives it, and is this the proper way, or should it have been before the pressure tank?”source ↗
“All my pipes in the crawl space are covered in spray foam so I can't trace the path they take down there.”source ↗
“My initial thought was some type of water softener. But it’s before the sediment filter so that doesn’t make sense.”source ↗
“Manual said to drill on a vertical section above a p-trap. I'm a little confused on where I can do it.”source ↗
“I tried but it won’t because that part is curved and that’s the most it will go normally. If I push it with extreme force, it will then be too far in to be tightened with the screw cap as it won’t be flush with the screw cap anymore. At the same time, it still wouldn’t be pushed in enough for the pipes to meet together.”source ↗
“It’s definitely all the way in. If I cut it, wouldn’t that mean it still wouldn’t be able to go in because it is a curved piece and also it would be missing that round piece at the end?”source ↗
“I’m sorry what’s wrong with this?”source ↗
“I’m not getting slow draining or anything, just looking under my sinks and saw this, thought I’d check in.”source ↗
“What the fuck kind of DIY drum trap is this? Is that just open on the top?”source ↗
Where this came up
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