ᐅ Hot Water from the Vent: Why Does It Happen?

Good evening!

Today, I tried to replace a kitchen faucet, but I was unable to do so. Since the shut-off valves there are outdated, I turned off the main valve. To prevent too much water from flowing into the kitchen, I opened the lowest valves, namely at the basement sink, to drain the system.

As I couldn’t manage to get the compression ring of the faucet over the four supply and return hoses, I reassembled everything and turned the water back on.

Since then, hot water has been continuously flowing from the air vent at the highest point of the system and into the funnel. So nothing is leaking anywhere, but I wonder why water is constantly flowing there. This never happened before. Does anyone have any idea? I can’t reach my plumber...

Matthias

There is dirt in the vent or the float is sticking. It could also be limescale. Try tapping on it. In the worst case, it needs to be replaced or disconnected. Nowadays, this is no longer commonly done.

Knocking won’t help. I’m still waiting for feedback from my installer. I don’t even know why that is there in the first place. And why is it no longer done today? Replacement will probably mean knocking off tiles...

Matthias

Pianist schrieb:

Knocking won’t help. I’m still waiting for my installer to get back to me.

Well, with that one, I wouldn’t knock—I’d ring the bell or give them a call.

I have tapped on the air vent and called the installer...

Then show a picture.
Usually, you can screw them on.

These things were used with old fixtures that didn’t have built-in check valves to prevent contaminated water from flowing back into the pipe in case of a leak.