Boiler losing pressure

[Ben2411]

First time post so go easy, ive had an ongoing issue with my boiler loosing pressure, ive had boiker chexked over and they suggest its a fault with pipework, ive checked for ceiling staining and around all radiators however all dry and no obvious signs, weve tried fernox f4 leak sealer still to no avail, boiler pressure will drop every 3-4 days max depending on use, has even needed topping up after 24hrs, we are almost atbthe point of paying a leak detection company to come and check the system over, im concerned they may find nothing, so hoping yiubguys may have some tips i could try, i am an electrician by trade so have a good understanding just wodnering if i may of missed anything, so any advice on how you guys would approach this would be much appreciated

 

[Ben2411]

Just tried a couple. Of things from above, topped pressure to 1.4 then isolated flow and return and within about 10 minutes has dropped to 1.0, boiler, ia this normal or far too fast, i disconnected condensate pipe below but no drips as yet

 

[ShaunCorbs]

Depends if the boiler was hot ?

 

[Ben2411]

It has been on fairly recent but pipework doesnt feel hot

 

[ShaunCorbs]

Then after this drop shouldn’t drop no more

 

[Ben2411]

Ok, so just had to. Pit heating back on as it was getting cold and when i opened the valves i noticed the pressure gauge went back up to 1.4, is this normal or point towards a boiler issue, will try again over nIght though

 

[ShaunCorbs]

Boilers at fault fixed price repair from ideal or new boiler hex is split

 

[Ben2411]

Hello guys, finally had a chance to update, last night i pressurised the boiler to 1.4 bar and shut off electrically and at the flow and return valves, within a few minutes it had dropped to just below 1 bar and by the morning, (10 hours later) was down to 0.8 bar,

When i then opened the valves it dropped further to 0.2bar and then required topping up,

Does this confirm the fault to be with the heat exchanger, can someone explain why the pressure would have dropped further to 0.2 bar?

 

[Ben2411]

I also but a small clear takeaway type container under the condensate pipe over night and this was about 1/3 - 1/2 full, no rain or other reason for the water.

 

[EvilDrPorkChop]

Sounds like you’ve got a leaking HEX and a leaking system somewhere.

When you opened the valves back up the pressure should have increased back to 1.4 bar (or there abouts) if the system was good. As that would of still held pressure.

 

[Ben2411]

That was my worry, i will carry out the test again but making sure all radiators are bled etc first, it appears the bulk of the leak is with the HEX, as wrote previosuly above the pressure did go back up when testing for a short amount of time