One cold-water tap on the second floor gives strongly mold-smelling/tasting water. There's no problem with any other tap in the house, hot or cold. There was a brief, slight improvement when I replaced the tap-set and the pipes under the sink, but it came back within a week, so the problem is further down the pipe. What is the best approach that doesn't involve a plumber? I'm considering shutting off the supply, draining the pipes, opening just the offending tap and the tap on the utility sink in the basement, and filling the cold-water pipes with Javex. The wife will close the lower tap when Javex starts coming through, and I'll stop pouring when the offending pipe, upstairs, overflows. Then, I'd let it sit for a few hours, flush the system and resume normal use. Or, is that a waste of time?
Answer:
Let's not put away that bleach bottle but let's not go into picking everything apart either. You'll find it easier to disassemble the drain at the bottom of the sink just before the trap. Now you can block it so anything (a gallon or so of bleach) poured into the sink can't drain away for an hour or so. You can then reclaim the bleach by capturing it in a dish under the sink. Your problem is not the tap but the overflow of the sink and the easiest way to clean that is to put bleach through it.
