Automatic Air release valve - replacement question

trackerman

Hi folks,

I have to replace my Automatic Air release valve in the Hotpress because it's leaking.

My system doesn't have a drain valve for some reason.

Do I need to drain the system ? or can I just shut off the attic feed tank (lift ballcock) and accept a little water spillage as the pressure normalises?

Thanks

Tracker

10-10-20

Hi, this recent post also asked the same question - it will be helpful for you too. 👍️

https://www.boards.ie/discussion/2058368742/fitting-an-expansion-vessel

trackerman

https://www.boards.ie/discussion/comment/122621988#Comment_122621988

Thanks 10-10-20

carveone

https://www.boards.ie/discussion/2058369229/automatic-air-release-valve-replacement-question

They do that alright. And then there's never a drain cock. It's not the worst thing to drain and flush anyway unless you're like me and the boiler is the high point in the system with a clogged AAV. That's annoying (and I won't touch boilers).

I remember years back changing valves to TRVs with my Dad without draining. We may have plugged the feed tank to try and pull more of a vacuum but mostly I think I just put my thumb on the pipe and used some towels (on carpet too). I had to cut the existing olive off so it's not as if we were just doing it quickly - it wasn't gushing out like.

Try it, see how crazy it gets and then make up your mind 😂