Help - Water pouring through hall ceiling

[vetinry]

I've just got back from a business trip and when I came into the hall, there was a puddle of water on the floor and a steady flow coming from the ceiling.
I went straight upstairs and found a lot of water in the airing cupboard directly under the cylinder and have quickly traced the source as some sort of vent valve on the top pipe of the water heating coil.
I have been doing some plumbing recently but not on the hot water circuit.
But I have had to drain down the central heating circuit a couple of times and indeed at the weekend, after refilling, I've not got heat from one of the downstairs radiators.
So, all in all, very confused. Has the vent valve (not sure what it's called) simply failed, or have I caused a different problem which has caused pressure build up in the hot water heating coil circuit.
The water heating control was off when I got in but the CH was on and most of radiators are warm.
Any help very much appreciated
Steve

 

[Billy Bob Bob]

is it a small brass finger thumb manual air vent?

 

[vetinry]

Hey gas man

It's got a little brass screw on the top but sat on top of a slightly larger (approx 1 inch diameter) barrel.
Is it an automatic air vent?

Steve

 

[Billy Bob Bob]

could be if its a aav might have burst

 

[vetinry]

So, can I just drain system down again, replace and refill?

I was just surprised how much water was coming out of it.

Am I likely to have caused this by doing some plumbing on the CH circuits, or more likely just co-incidence?

Thanks

Steve

 

[Billy Bob Bob]

yes drain down and replace and yes you may have inadvertently caused it but thats the nature of aav s they have a Schroeder valve that sticks when you drain down and leaks when you re fill

 

[vetinry]

OK - I shall get a new one tomorrow and get it fitted asap.

Thanks very much for your help

Much appreciated

Steve

 

[Billy Bob Bob]

dont forget thers 2 different thread types 3/8 bsp and 1/2 bsp

 

[justlead1]

Hi. No need to drain down to much just whip one out and the new one back sharpish. (PTFE around thread)

 

[vetinry]

I've sent my wife to plumbers merchant with the part to ensure we get the right size - wasn't sure which thread it was.

I've just drained the system down sufficiently to get the AAV off and thanks for the reminder to wrap the thread in PTFE before replacing.

Now just have to get the heating back on so that I can dry out ceiling etc.

Cheers

Steve