Z-Wave water shutoff valves; watercop, dome etc. Do you get air coming from faucets after being closed?

This may be more appropriate in the Lounge area but I figured it is similar to a light flickering.

I have a relatively new Watercop installed and running fine with my C7. However I noticed when testing and today where a sink overflowed, when the valve is closed (in response to the sensed leak). After the overflow was remedied and the WaterCop is turned on again, several faucets spit some air when first turned.

Has anyone had a similar experience with their automatic valves?


It is similar to a light flickering during an electrical storm...
When a valve is closed, the pipe past the valve is either filled with water or filled with air or some combination of these. If it is not filled with water, there is some air in the pipe which has to go somewhere before the pipe returns to the normal state of being filled with water.


Thanks for the response.

My situation is a little different. I have city water having relatively high water pressure. The air "spitting" only occurs one time (at several fixtures) after water the WaterCop has been off for 20 to 30 minutes then turned on. I have a working theory but would like to know if others have experienced the same.

That sputtering is typical behavior anytime an upstream valve is closed and reopened.

When a valve is closed, existing water in the downstream pipes "settles" over time, depending on what other taps are opened or closed on different levels of the home, where the vents are, etc.

But it has nothing at all to do with whether or not the valve is automated.

ETA: removed vents reference (brain fart). That "settling" process introduces air in the system - sometimes just a little, sometimes a lot.

I think it's because there is some water flow when the shutoff valve is off. Say, a toilet is flushed or is leaking, or a water faucet is inadvertently turned on.

I was thinking of something similar. My theory is the hot water in the pipes cools, contracts and "sucks" in air through the faucet fixtures which are designed to stop water flow only in the out direction. Again this is just a theory at this point.

I suspect the automated valve and manual valve should provide the same results. The only difference is the automated valve is slower than the manual (automated time ~ 4 seconds).

Yeah, I think @velvetfoot is correct. I have 3 watercorp valves and they have this behavior only when there's water running while valve closing or opening.
You can easily test it.

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Thanks for the report. I may test it some time but I'm not worried about it. It does help to know others see the same thing.

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in both my houses i have the same behaviour.. less if the system is shut only briefly..same when city shuts off water for any reason


Let me just add here that you don't want to, somehow, have your water shut down during a water softener regen. I've never had brine coming out of my faucets before, lol. Just a heads up.