oh dear

[breezer]

can anyone tell me what

this is, and what does it do?

Ours has just "sprung a leak" water all inside the boiler, taken the rcd out, (now dissed the boiler so we can have some electricity)


we have BG coming tomorrow (tues) but i want to know if i am being given any "b.s."

ours is a combi (puma, not sure of model #) just recently it has been going into "lock out" (helpful that, doesn't tell you anything) and ocasaionally lets off steam from the brass thing (so i wonder is that the prv?) anyway, in desperation today mrs breezer called bg, who sent out transco, the transco man could find othing wrong, other than it had not been serviced properly, but about 1/2 hr ago we lost all things electric (aren't emergency lights marvelous!)

what i suppose i am trying to ask is any sugestions what happened? I figure it must be a saftey device of some description but why did it "go"

 

[oilman]

It's an automatic air vent. You can stop it leaking by screwing up th plastic cap in the picture.

Not sure what safety devices you are referring to, but if water's got everywhere it could be anything. (then again it could be I just don't know anything about gas boilers).

What pressure did the gauge indicate when the steam came out? It sounds like the pressure vessel is u/s. Depress the air valve and see if water comes out, if so that's one of the problems.

AAV's are available for around £5 or less.

 

[breezer]

thanks oil man, i figured that (what i now know is the auto air vent) is a saftey device. is its only job to vent excess air? (suppose excess water is a bonus then?)

 

[oilman]

The AAV is just a convenience device, it works fine when it's new, and makes life easy when filling a system, and gives people a nasty shock if they try to do things with radiators without draining the system. So instead of the air pressure holding the water in and it leaking slowly, it dumps all over them. Unless of course you do the plastic cap up.

However, its main long term function is to wait till no one's looking, and leak water anywhere it can.

I suppose we ought to treat them as a servicable device. Some have a second valve underneath, which allows the AAV to be unscrewed and replaced, without draining the system, but boiler makers save money by leaving this bit out. Most thoughtful.

 

[breezer]

However, its main long term function is to wait till no one's looking, and leak water anywhere it can.

so i noticed.

would you say it is "normal" to leave the cap slightly undone?

any thoughts as to why it did this (apart from the fact thats all they seem to do?)

 

[oilman]

Yes, it's "normal" to leave it slightly open, and I do it, but I suspect there's some lazyness about it.

They probably leak for a couple of reasons, one is contamination on the seat at some time which allows a continual weep, and the other might be float failure.

Don't let the gas man take it away, have a look at it and see if you can find out what the cause was, I would be interested to know what it was.

 

[DP]

The valve MUST always be upright for it to function correctly. The Puma has a similar valve within the boiler casing factory fitted so cannot understand need for another. The angle the valve is sitting at will indeed cause it to misbehave as mentioned in the original post. A small float lives within the valve body. The float rides on surface of water in the valve body. If valve is angled, the float may or may not rise to the highest point in the valve body to seal the vent.

Boiler letting off steam indicates lack of circulation

Transco are not British Gas. Transco attends gas leaks and BG (deep blue vans) provide maintainance contracts on heating systems.

 

[breezer]

Transco are not British Gas. Transco attends gas leaks and BG (deep blue vans) provide maintainance contracts on heating systems.

I know Transco are not b.g, but bg sent transco as mrs breezer was a bit "upset" shall we say, and transco were here within 30mins of mrs breezer calling

Thanks DP, perhaps its the angle of which the picture looks, (but the valve is vertical)


I am just curious to know why it decided to "dump everthing", i left a bucket under the boiler last night and i have just emptied it as it was full, the little screw valve is shut and there is still a slight drip from somewhere.
.

 

[breezer]

bg man has fitted new auto air release valve, heating now back up and running, they are coming back tomorrow (weds) to service it again.

Bg will come out "after hours" but only as a "plaster service" (in other words they will stop a leak or whatever, but not fix it, but will rebook it back in next day to be fixed properly)

 

[oilman]

Did you manage to get hold of the AAV from the service guy?