Water dripping from Boiler - PLEASE HELP

Looks like the DHW heat exchanger.

 

Er, can that big nut be tightened a tad?

 

That's what I was going to suggest, but was just waiting for a gas guy to comment.

Could try tightening it up a little, but don't over tighten. drain the system at the drain points ant isolate the supply.

If it dosent work and still drips, then best to remove the compression nut and joint and apply PTFE tape around the olive, or apply potable jointing compound.

 

Keston boilers avoid them like the plague

 

Ahmed, has anything happened to the boiler recently that could have caused that leak? It's a surprisingly fast drip.

Anyways, it looks as tho' it's either that the joint there has loosened somehow (or the washer has collapsed for some reason) or else it's the actual 'welded' join from that threaded part to the exchanger body.

So, definitely worth getting a well-fitting spanner and turning that nut slightly clockwise - less than one nut 'flat'. It might be easy to turn (good) or quite stiff (that's ok). I don't think you have anything to lose by doing this - it'll either cure it or it won't. If it's really stiff, don't force it.

If that doesn't work, try and have a very close look at where the drip is forming - is it coming from 'under' that nut at the back? Or is it coming from the the threaded pipe that's coming from that block thingy - from where that threaded pipe joins the block?

Almost certainly the former. Ie - the nut. In which case, if you feel competent to do so, you can shut off the mains, depressurise the system, undo that nut (catch any water), check the O ring that's almost certainly there, replace it (or coat it in jointing compound if it ain't actually broken) and retighten the nut.

If you need further details on how to do this, then you need a plumber

 

The seal between the pipe and the heat exchanger has degraded. Isolate the mains supply , disconnect it and clean the faces, replace with a new washer and re-assemble. Beware of tightening up the joint as it willcompletely crush it and the leak will get worse. Use a good quality fibre washer and do not overtighten.