About a year ago, I discovered the horizontal section of our kitchen waste pipe had a crack along the top surface, about 6 inches long. I can only conclude that is was damaged during or before installation. No idea, at least
12 years ago, before we bought the house.
However, I've become recently annoyed by gurgling sounds, usually when the dishwasher is running, but sometimes in the middle of the night, hours after anything has been tipped or poured down the drain.
I investigated, and concluded, there must be a vacuum being formed, by the waste water running away. I'm sure the problem started, when I replaced the damaged waste pipe. Would make sense, as that crack was not allowing the vacuum to form.
I did some investigation, and discovered this:-
I ordered one, and replaced the existing U-Bend under our sink with it.
The gurgling didn't stop. I removed the little screw on cap, that covers the air valve, and also exposes the drainage system to the open air. There was a hiss, as air rushed in, and immediately the gurgling stopped.
However, I assume it's supposed to be used with that cap screwed on ? Without it, waste water leaks out.
Does anybody have any experience of this, or similar devices ? Is the air valve faulty, or possibly underrated for my problem ?
TIA