For what its worth i have one bathroom that will get sanded if anything gets past the meter.

Its happened several times over the years. I keep new toilet flush valves and sink aerators on hand at all times for when this happens.

I would start by flushing the tub faucets and or remove the shower head. Then remove the sink aerators and open flush then remove the toilet flush valve and doing an open line flush.

Then replace the toilet flush valve and sink aerator.

quote:

Could be calcium buildup on the commode shutoff valve or the fill mechanism itself.

If he's got a clogged aerator it's entirely possible that he's got the same issue inside the fill valve of the toilet.

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Just fixed a problem like this. Sediment in the lines. Changed out fill valve in toilet, cleaned aerator and drained the lines to the water heater. Back to normal.