Leaking valve on boiler piping

[TanyaB]

Hello - Could anybody identify what this valve is please. It has started leaking a lot and is on the hot water pipe coming out of the boiler, which is Boulter Economy standard oil boiler, vented system. It has a nut on top that was half a turn undone so I tightened it hoping it would stop. It hasn't.

Thankyou

 

[Dotty]

It's a pressure relief valve.

It'll need replaced.

 

[quality]

what he said

 

[TanyaB]

Thanks very much :smiley2:

 

[stevetheplumber]

dont know if you have to have it on oil but on gas i usually plug them

 

[Best]

I would rather put a proper 3bar PRV on.
Those relief valves, as in photo are just tightened up on their adjustment nut to a guessed tightness for the pressure blow off.
The O ring seal in them just perishes with heat

 

[Dotty]

I would rather put a proper 3bar PRV on.
Those relief valves, as in photo are just tightened up on their adjustment nut to a guessed tightness for the pressure blow off.
The O ring seal in them just perishes with heat

I agree, them things are awful.

 

[Best]

I agree, them things are awful.

Yes, everything is so wrong about them! If they ever did open under pressure I bet they would fail to seal again at all and flood the place.
I remember it was obviously a cost thing, - at least about 4 times the price between a 1/2" valve like that and a proper 3bar valve.
I don't think I have ever seen a PRV opening due to a boiler being over pressured when frozen pipes, or in fact any vent/feed blocked.