Newly remodeled lower level and never a prior problem. When turning on the bathtub, an immediate glob of brown water first, then immediately clear water. Same with a kitchen sink. Numerous plumbers can not figure it out. Lower level is naturally on a slab with a portion (small square) cut out for the separate drains. These are the only 2 faucets throughout the house doing this. Unbelievable question. With the high pressure of water, is there any possibility that it could be siphoning from the drain??

No chance it's siphoning. Sounds more like a steel screw or fitting that's starting to get rusty.



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I agree with Steve, Galvanized nipples could be the cause this rust problem.



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Thanks for both replies. All copper/pex water lines, no galvanized. And, as I had mentioned, the only 2 faucets giving me problems.

The tub could have a galvanized nipple holding the spout, but not sure where one could be in the kitchen, but it does appear that there is one SOMEWHERE.

Thanks HJ. I did forget a short galvanized tub spout coupling. Everything is new. The sink connection is brass to stainless lines. A few plumbers have felt it was from lack of use. I try it every other day, always with the same results. Even flushed the hot water tank. Absolutely makes no sense!!

an immediate glob of brown water first
Can you quantify the amount of brown water, in ounces (or time at full flow) until clear?

Is it worse or better running all hot or all cold water?

Have you disconnected the fixture supplies (on the kitchen sink, at least) to see what comes straight from the plumbing fittings?

Have you shut off the water heater and shut one fixture stop or the other?

When I had this on a new spa tub, I went hunting, and found that the plumber had used a short galvanized nipple between the diverter and the valves. Barely visible between brass supply lines and fittings. He replaced it.

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Links to the State of Wisconsin Plumbing Code:
[docs.legis.wisconsin.gov]
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I am not a plumber.
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I had this in one property that I own, someone had used a black steel nipple inside the tub spout! Symptom was a spurt of rusty water when turning on the tub each time.

If it is not the whole system, then it is somewhere close to the faucet having the problem. The sooner it happens when you turn on the faucet, the closer it is to the faucet.

Hey guys, thank you so much for all the input. I'm going on a fishing expedition tomorrow to see if there are any black pipe or galvanized nipples on either the tub spout or the water stops under the sink. I'm keeping my fingers crossed. Thanks again



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