What could this thing be

[phill1305]

Hi,

first ever post on here and hoping it gives me a chance to add a photo...

In my airing cupboard I have a load of pipes as expected but one has a small device on the end of the pipe. Not sure what it could be or what it does. I have unscrewed the cap which has a small hole in the side and a piece of rubber in the cap. The thing that is attached to the pipes has a small hole in the top but thats about it. I was expecting water to spray out when removing the cap but nothing happened. Would be great if I could use it to bleed air out the system.

Thanks,
Phill

 

[paulwrx]

could be a auto air vent

 

[45yearsagasman]

That's not an auto air vent but it is a manual one.The knurled cap can be loosened about a turn and air will come out(if you're lucky)and then re tightened.Sometimes the rubber washer under the cap sticks.Trying to remove the stuck washer sometimes results in a nice little water feature that you were not expecting.

 

[gigz]

Could be blocked with lime, take cap off and use a pin in the hole to unblock it, you will probably get air out before the water comes. P.S. you could be there a while if there's a lot of air in the system.