I have a hose bib, with a vacuum breaker, then a garden hose.

In the past, when I turn off the hose bib, there would be water draining out of the vacuum breaker to relieve the pressure, that's working as designed.

I noticed yesterday, that with the hose bib on, and I pulled the trigger on the garden hose nozzle to mix some stucco, as soon as I let the finger off the trigger, water squirts out on the sides of the vacuum breake, through the tiny holes all around, and quite strong, got me wet. In fact, every time I took my finger off the hose nozzle trigger, water squirts out. It has never done that before. Is the vacuum breaker breaking? What is causing this?

It is not a leak between the breaker and the hose, or between the hose and the breaker. I double checked.



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The hose is expanding from the water pressure. When you shut the nozzle off, it creates a momentary higher pressure in the hose and the vacuum breaker "opens" to relieve it just like it is supposed to do.

My armchair diagnosis would be this: the breaker should only activate/relieve under vacuum. Since yours is leaking under pressure, there is a problem with the poppet seating properly or the poppet washer has failed and no longer seals.