Throttling faucet makes water cloudy

ChrisJ

I've got a small faucet on my kitchen sink plumbed into a water filter. It's just a carbon filter.

If I run it fast the water is crystal clear but if I run it slow, so you can hear the valve sing the water becomes cloudy but clears up if you let it sit for a short time.

I assume this is air? But from where there's no aerator? Curious what exactly is going on.

mattmia2

probably more contact with the air in a smaller diameter column.

there is air dissolved in municipal water that will come out with increased temp and reduced pressure. maybe it warms faster in the smaller stream

EdTheHeaterMan

Boyle's Law of dissolved gasses will explain this.

With the change of pressure happening at the valve when it is partially closed, the water pressure is rapidly dropping at that point whar the water exits the pressurized piping system. That location is where the pressure drop allows the dissolved gasses to exit and form micro bubbles in the water in the glass.

When the valve is full open, the pressure drop happens further inside the piping system (maybe near the filter) causing the micro bubbles to be released before they reach the glass. Those micro bubbles can connect with other micro bubbles to become larger bubbles that exit the water more rapidly when the water exits the valve.

hot_rod

Cavitation is another possibility. As flow is restricted

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through a valve, pipe, any device you can get vapor pockets forming. Usually there is a noise is associated with cavitation.

It can happen in a restriction, across a rough surface, at your garden hose nozzle, or on the blades of a propeller.

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If it is entrained air in the water supply, and there is in public water supplies, it comes out of solution as the pressure is lowered on the water, like when the faucet is opened. If you water pressure is 60 psi, as soon as a faucet opens thatn pressure is released and the bubbles come out of solution.

Any idea of what your water pressure is?

ChrisJ

https://forum.heatinghelp.com/discussion/comment/1806949#Comment_1806949

It's 88-90 before my prv and then 60ish.