Boiler losing pressure and found a leak

[Gary_P]

Hello,

This is my first message here and I'd be grateful for any tips or pointers!

A few months ago, my boiler pressure dropped to the point that it cut out until the filling loop was used to re-pressurise it. Someone else did this for me as this is my first home and I had no idea. I have been periodically monitoring the pressure and it has been falling slowly ever since. I have done some searching and I understand that the pressure release valve is often to blame for a system de-pressurising. I cannot do the bag on the pipe test as I live on the second floor and therefore cannot get near where I think the pipe is on the outside wall.

In order to get the pressure problem solved before the boiler cut out again, I thought I'd use the filling loop to boost the pressure in the system. In doing so, I noticed a load of wet limescale around a strange looking device in the airing cupboard amongst all the pipes around the hot water tank, which is nowhere near the boiler. The person who showed me the filling loop obviously did not spot the leak at the time. My questions are, is this item likely to be the cause of the system pressure dropping over a prolonged period and what is it? Also, is repair going to be expensive?



I don't know whether it's relevant, but my hot water is partially supplied by a solar panel.

Thanks for any and all help in advance and I appreciate this is a big ask for a first post!

Gary

 

[kimbo]

Sounds like the expansion vessel needs recharging or the prv is letting by. Either way you need an engineer out to deal with it

 

[wattsie1987]

Looks like the tundish between d1 and d2 on an unvented cylinder to me if it is it will be unrelated to boiler pressure dropping but also needs looking at asap as that is one of the safety devices discharging. Best bet is get a professional to have a look and offer you advise on both matters.

 

[village idiot]

have you actually been able to confirm that there is a ''blow-off'' pipe at the outside wall (even if you can't get to it?
It could also be the case that the tundish in picture actually serves water discharged from a PRV. In as much as they are commonly used for D1 & D2 in unvented cylinders, in some cases, where flats are located in places where access to an outside wall directly from boiler is restricted, a tundish can be used. That way, if there is a discharge, you will notice from tundish. If this is the case, you not likely to find a pipe on the outside wall

 

[AWheating]

it may be the heating tundish tho hepvo valves are not supposed to be used on heating systems for some strange reason.

post a picture or two of the entire airing cupboard.

 

[nysk2008]

re-pressurise and monitor system pressure, if tundish leaks repressurise expansion, if continues to dischsrge the vessell is gone

 

[village idiot]

it may be the heating tundish tho hepvo valves are not supposed to be used on heating systems for some strange reason.

post a picture or two of the entire airing cupboard.

if I'm faced with 'difficulty' dish charging PRV blow off to outside wall, I'll gladly use Tundish and finish off with an overflow plastic pipe kinda thingy, then route to 32 or 40mm waste pipe. If the boiler manufacturer or someone on here can convince me why using the plastic pipe is such a bad idea, then I'm prepared to listen

 

[Gray0689]

Either expansion vessel or safety valve passing
Get a plumber in with unvented ticket to fix

 

[AWheating]

if I'm faced with 'difficulty' dish charging PRV blow off to outside wall, I'll gladly use Tundish and finish off with an overflow plastic pipe kinda thingy, then route to 32 or 40mm waste pipe. If the boiler manufacturer or someone on here can convince me why using the plastic pipe is such a bad idea, then I'm prepared to listen

its states on the hepvo instructions that is should not be used for heating systems, i would also run to waste if i could not get else where.