Boiler pressure dropping & how to find the leak

[Geeky]

Hi All

Looking for some advice. Since I switched the heating back on a few weeks ago, the pressure on my one year old Vaillant Ecotec boiler has been dropping by one tenth of a bar each day - so from 1.5 to 1.4 to 1.3 and so on right down to 0.9 this morning when cold. Pressure rises by a few tenths when the heating is on but then drops again when cold. I can't see anything dripping from the pressure relief valve.

Worst case scenario is a leak under my newly laid laminate floor or behind my newly fitted kitchen cabinets! If this is the case, do any of you have any advice on or experience of leak detection companies? As I understand it, they use gas and thermal imaging to find small leaks without having to pull the whole house apart.

I'm waiting for a plumber/heating engineer to call me back, but in the meantime I'd really appreciate any comments or advice.

Cheers!

 

[Centralheatking]

Depending on the layout of the heating system if might be an idea to say blank off part/half of the system - eg upstairs from downstairs or 1 or 2 rads on a longer leg and see if pressure still drops then you could begin to focus on the exact location to tear up.

Or shoot it up with loads of mains pressure with the boiler isolated and see if the leak can be made worse and show its location.

centralheatking

 

[Geeky]

Centralheating, the boiler guy mentioned isolating upstairs from downstairs - sounded like a bit of hassle as it apparently involves cutting and capping off the pipe then presumably having to join them again afterwards ... ? But will mention this to my builder, plus the idea of upping the pressure to identify the leak. Thanks for the tips.

 

[Geeky]

Well here's an update as promised. As the weather got colder and we had the heating on more, the leak got worse and we were topping up every other day. I had my builder put some Fernox SuperConcentrate in and (fingers crossed) it seems to have worked and 2/3 days later the pressure seems to be holding up. If it starts leaking again, by the way, would you put some more Fernox in?

I did ring some leak detection companies - one national company quoted £700 plus VAT plus materials and a London based company just admitted it would be £1000 in all . This is for a small two bed house with only 6 rads, none buried in concrete. Sounds like a good business to be in.

Anyway, my builder reckons if the leak reappears it's only a day's work for him to pull up floors, find and fix leak, and make good - £120 plus materials, so I'm feeling better all round.

Thanks for all your suggestions too which have improved my knowledge and helped me get this sorted.

 

[justlead1]

Hi. Is the new laminate floor fitted over an existing wood board floor? And were any boards nailed or screwed prior to new laminate floor?

 

[Geeky]

Hi Justlead1 - laminate is on hardboard/chipboard - one or two bits were replaced before the laminate was laid. Are you thinking screws through pipes? Someone did suggest this. It's possible, but my builders are pretty good so I'm hoping they wouldn't make this kind of mistake. If the leak comes back and we have to take up the floor, I guess we'll find out ...

 

[justlead1]

Get some pressure testing done before panicking about leaks. Your plumber can isolate expansion vessel, purge any air from system and pressure test. When testing, be aware that temp change has an effect on gauge readings, the longer you can leave it on test the more accurate the results. Good Luck

 

[Geeky]

Get some pressure testing done before panicking about leaks. Your plumber can isolate expansion vessel, purge any air from system and pressure test. When testing, be aware that temp change has an effect on gauge readings, the longer you can leave it on test the more accurate the results. Good Luck

Excuse my ignorance Justlead but what does pressure testing do (if not find leaks)?