Boiler leak

Another_Level

Haley00 said:

The boiler has also been serviced in the last month and they detected no leak nor any problems and was under the illusion that the service would sort it!  The condense pipe is above my conservatory so I can hear it when it drips so I know it’s not that that’s the problem with that. 

Hopefully they serviced the expansion vessel. its expected in a service unless the part's manufacture say different 

At the end of the day it's down to the skill of the person servicing the gas boiler and its attached serviceable items. 

Its a process of elimination, eliminating faults in the wall mounted boiler are easy 

Haley00

This is under the boiler 

Haley00

If it is in the rads pipe work how do I fix it? 

Bendy_House

Haley00 said:

If it is in the rads pipe work how do I fix it? 

By finding it. The 'fix' will be easy in comparison...

Bendy_House

The pipes are as shown (pretty sure... :-)  )

The two orange-arrowed black knobs are the valves in question. I'm guessing you turn them clockwise to shut them off, and I'm also guessing that they'll come to a halt in the closed position. I'm further guessing that they'll be stiff to start turning, and perhaps stiff throughout.

But, I'm also guessing that you should be able to turn them without any concern - they are usually pretty reliable.

Are you going to try this? If so, BOILER OFF and COLD, and pressure tweaked up to, say, between 1.5 and 2 bar (this is higher than normal, but should encourage any leak to go faster = better results. You don't really want to go above 2 bar. Once your test is over, use a rad bleed screw to bring the pressure back down to 'normal', which I'd suggest is around 1.2 bar).

Note accurately the pressure reading - take a photo - and then shut off both these black valves. Make sure they turn through a full 90o.

Leave overnight or during most of a day. Check reading - any change? Note it down. Open valves - but keep an eye on the pressure as you open the first one - any flicker/change?

Open both valves, reduce pressure using rad bleed screw, turn on boiler.

Bendy_House

Have you told us what the pressure reading does in normal use? Ie when the boiler heats up from cold - and changes? If so, what?

And... have you actually tied a wee plastic bag over the end of the safety discharge pipe with a rubber band?

Haley00

Yep done allll that with the plastic bag 
will try isolating the boiler. I have no heating anyway so turning it off isn’t going to be a problem. As for ‘finding it’ thsts the whole point, I can’t 🤷‍♀️

Haley00

I have had somebody out to service the boiler and they couldn’t detect anything.
I have tested the PRV ( put bag over pipe) it wasn’t that.
have listened out for condensed pipe, it only drips when heating is on.
Have had the radiators flushed and that special sealant put through it that is meant to fix small holes, thst hasn’t worked. 

I have had 2 separate workmen go under the floor to find a leak and couldn’t detect any.
there are no damp/water stains on any of the ways or the ceilings. 

I am now all out of suggestions other then trying to isolate the boiler. Thanks I will give this a try 

Haley00

I have also had the expansion value thing pumped up 

bris

A crack in the heat exchanger, the water goes out through the condensat pipe so you can't see a leak. 

Put a container under it, disconnect the condensate pipe from under the boiler and see if anything drips from it with the heating off.