I have copper water supply lines. I have been experiencing severly reduced pressure at the Kitchen sink faucet on the cold side only.
I checked the lines in the basement the cold supply line for the sink has a shutout valve that is heavy corroded. Lots of white bumpy stuff on the valve and lots of green colored corrosion on the surrounding pipe.
Is it possible this pipe has corroded on the inside and the debris is blocking the water flow?
Mike
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Replies
Green on the outside of the pipe is probably a plumber not wiping off his (acid) flux. Can cause pinhole leaks but won't clog pipes to my knowledge.
How hard is your water? White stuff is probably minerals from evaporated water that leaks past the valve seal. Mineral deposits can clog pipes just like hardening arteries, but I don't understand how it could only happen to one pipe.
Do you know for sure that the reduced flow isn't caused by the tap itself?
Regards,
Tim Ruttan
I've seen hard water deposit narrow a water service line down to 1/4" ID. If you don't wan tot cut into the plumbing just yet: Put a pressure on a hose bib (they sell them with a hose thread) and check the pressure drop with different amounts of water usage. You shouldn't see much pressure drop until you are using 10 gpm or more (2 or 3 fixtures running).David Thomas Overlooking Cook Inlet in Kenai, Alaska
Sounds like it could be an electro-chemical reaction caused by dissimilar metals. Does this valve look like steel rather than bronze? Did you take the strainer out of the faucet and try the flow without it?
Al Mollitor, Sharon MA
I would have suggested the aireator on the faucet as well but he said cold side only. You have copper in the house, but what about the main line from the street? Is it galvanized? Perhaps you only see crud in the line making it to the kitchen because it is on the first floor?
Thanks for all the advice.
Thing is the bathroom faucet on the 1st level of the house works fine. Toilet, DW, and laundry all seem fine. The upper level fixtures feed of the same main supply pipe AFTER the sink trunk, and they all work fine. That's why I suspect the problem may not be in the main supply line, but just in the trunk line to the sink.
I also had a guy from the city come out and check the line from the street. It's OK other than the fact that it's only a 1/2" pipe. Told me it will cost me $3,000 to have a larger diameter pipe put in. Ouch!
Seems like it can be one of 2 things: a bad faucet, or debris in the copper pipe between the main supply pipe and the sink. I guess I'll dissassemble the Kitchen faucet and turn the water on briefly to blow any debris out of the line. If that doesn't work I'll replace the faucet.
Again, thanks for the suggestions.
Mike
Another possibility is that in the past your house had galvanized pipe, and somebody did a partial copper re-pipe. What they'd do is replace the horizontal runs in the basement or crawl space with copper, and leave the galv going up into the house. Perhaps you can poke around with a magnet on a stick and make sure....
-- J.S.
John,
Thanks for the idea.
It appears they replaced all the water lines with copper in the 1970's when they remodeled the Kitchen and Bathrooms. The copper lines come all the way up under the base cabinet to the sink.
After I figure out the problem I'll post a follow up.
Mike
Mike
I,m making a guess based on your info so far. If you have a shutoff "under" the sink it could be partially plugged with debris or a rock? If you turn off your main shutoff and remove the stem you might want to try flushing some water into a 5 gal. bucket. If this does not turn up debris at least it will show you how much flow you have to that point then tackle the faucet if thats where it points
Kevin
This is sometimes simply the faucet valve itself.
That is generally the narrowest passage, and therefore the weakest link.
I would look for something real simple like the washer broke up and has clogged the pipe. Shut of the water to the house and the take this encrusted valve apart. I'm betting you will find a mess of bits inside.
Mike,
If that valve with the white and green stuff is the only valve that you've seen so corroded, i would suspect that it is a different metal than copper. if so it should be replaced.
Thanks for all the help Guys! Enjoy your Holiday.
Mike
A buddy of mine had a similar problem in his relatively new house. Grit and small rocks were making their way through the cold water system (but were settling out in the hot water tank so no problems with hot. The solution was to take apart and clean the offending valves. I was amazed at the size of pebble that was making it up to the second floor!
Pete