Boiler leaking from this part....

[Dushami]

Finally found out where my boiler was leaking from. See attached picture, it’s from underneath & it’s the valve on the right. It’s dripping from the bit that’s screwed in, the brass part, not leaking out the screw itself.
Is the only option to replace it? It’s a Vokera MyNute system boiler.

Thanks!
Scott.

 

[Dushami]

The heating has just come on & it’s now stopped leaking. I guess some bit inside has expanded & it’s now sealed?
I’ve been topping this thing up for a year & I guess any of that sentinel stuff would be diluted away to nothing. I’ve never managed to find out where this leak is coming from because I’ve never looked when it’s cold!
I assume it’s vital to replace this inhibitor once the valve is replaced? I mean, is it possible that I’ve already knackered the system by running for a year on probably water alone?

 

[terryplumb]

Can't tell from pic where its leaking from ,nor from your description .is it where the brass valve meets the vertical copper pipe ,at the joint ? Can't tell if its a compression fitting ,which is the usual type of joint ,or if its a threaded joint. Either way the joint can be remade. Take a pic at an angle ,side on rather than head on. If its a compression joint you may be able to tighten a bit . continually running fresh water into the c/ heating system will speed up the corrosion process and weaken the Inhibitor concentration .so put more inhibitor in.

 

[ianmcd]

These isolation valves leak for fun , replace both of them at the same time, and never use them as valves to isolate the boiler or they will start leaking , yes most leak when cold and stop when they heat up and expand

 

[Dushami]

I found an online manual & now understand what you mean by isolation valve. I’m not aware of this ever being used to isolate the boiler in all the time I’ve been here. My old man is up for a visit at the weekend. He’s a retired plumber back when Noah had a few issues, but I’m sure he’ll be able to swap the valve over.
Terry - it’s dripping at the part of the valve that you can turn. I didn’t notice or understand what this valve was for.
Thanks guys.

 

[Dushami]

Ok, so I’ve got the new valve and small fibre washer. That should fix the boiler leak. I’ve noticed that the outside pipe that bends in towards the wall has been leaking. In the last service I had, April I think, the PRV got replaced because I mention this water lying outside. The thing is, that valve might have been leaking, but I’m not sure this water is coming from the same place. I have a Sterling tempest with 130 litre hot water capacity. Attached to this horizontally is a Zimlet 110 Ultra Pro which is 10 years old according to date of manufacture. Anyway, when I press the bicycle style valve on it, no air comes out. I also placed a piece of bog paper over a black cone shaped plastic hole. You can see this in the photo I’ve attached. This bog paper was soaking wet this morning. How can I tell if the expansion vessel is OK? I have a pump, so can repressurise it. It seems like the membrane of this vessel can be replaced. Any further advice?

 

[John D v2.0]

Shouldn't be really pressing the bicycle valve, and there should have been a cap on the valve before. If no pressure left then no where for the expansion volume to go except where the paper is.
Once you get someone in (G3 of course) they will isolate and open the drain for the pipework and vessel, pump the vessel to the correct charge pressure, and then recommission the system. If any water comes out the valve then the vessel would need repairing and the same procedure and recommissioning.

 

[Dushami]

I know, but it’s like a red button that says “don’t press”, everyone eventually presses. I’m glad you mentioned G3, I’ll be calling around a few companies tomorrow. I have a small list of things for the lucky winner to do. Everything more or less works, but I’ve a feeling that once the leaking valve is fixed & this expansion tank is fixed, the radiators need balanced. They are uniform in terms of heat ie no cold spots, but some are hotter than others. I will also ask them to fit a magnetic device eg magnaclean or similar. I’ll take advice on the state of the water that comes out of the system as to whether it may benefit from a flush. Thanks for your reply.