In my basement I have a refrigerant line that goes from my HVAC evaporator unit inside the furnace ductwork to the condenser unit outside the house. The high pressure side is insulated, but the low pressure side is not. When the temperature gets really cold outside, water vapor condenses on the low pressure line and drips onto the floor. However, because this is pure water, it does not leave behind any water stains.
The presence of water stains on the concrete is likely to indicate that the drips contain mineral content.
I live in an area subject to radon, so I have vent pipes leading from my sumps to the roof. However, the sumps have removable covers What surprises me about the OP's installation is that the pipe seems to be be cemented into the floor with no access.
Unlike my copper refrigerant tube that conducts heat and cold quite well, a PVC pipe is a decent insullator, so I would be surprised if it could get cold enough to condense water vapor unless the humidity is quite high in the basement. If that is the case, getting a dehumidifier might be the answer.
In any even, the key to solving the problem will be to figure out exactly when the water is leaking. Hopefully, a water leak sensor can tell you that.
Not necessarily, concrete has a lot of unbound minerals (probably not the right term). When wet it causes or aggravates fluorescence typical of concrete.
I know this because we recently had a water leak in the cellar. The wet area, as it dried left a white residue. In some cases it looked similar to cotton candy.
True- new concrete is subject to efflorescence. As wet concrete dries, soluble salts migrate to the surface. However, since the water leak is so slight, I am not certain that sufficient water is present to cause this effect. However, you may be correct.
It seems mainly ground saturation coming through the wall and dripping along the pipe (pipe not actually leaking). You can tell by the way the staining is right below that caulk or whatever it is. Do you know how far below ground level that is? It may be worth just digging the area out and having it sealed right. As said above, leaks like that can cause problems for the foundation as well as for sellers..
Your probably correct. My response was prompted by my recent experience with a water leak. The concrete was saturated (if that is a proper term). As it dried around the wet dry line was white fuzz, looked like soap suds (not cotton candy as I previously mentioned). Had almost no actual content.
I don't disagree however my recent experience with "ground water" was that is came in at the base of the wall between the wall and the floor. I'm defiantly not a concrete structure engineer but it would seem if the water source was ground water, some would be coming in at the base of the wall.
A test I would definitely perform is to shut off all water in the house, then watch the water meter for continued flow (even if very small).
BTW does the tag on the pipe hold any useful information?
