Leak sealer needed

[trevorbayliss]

I think i need to use a leak sealer on a pressure drop issue on a combo.

There is no sign of a leak and it is happening over many months. I think the pressure gets low after about 3 months.

The whole downstairs area is laminate so i imagine the leak is under the ground floor but i don't want to rip it all up.

So is a sealer a good idea and is it ok to add it via the boiler filter.

 

[Madrab]

Nope, it get into everything (plate hex etc) and really isn't a good option longterm IMO.

 

[durhamplumber]

losing few points over 3 month.leave it

 

[andytw]

For a slow leak it's probably worth going around each radiator and tighten the bleed valve and it's fitting and the opposite end blanking plug. Then the valve nuts and most importantly the valve spindle nuts. All of these can leak but the water can evaporate before you see it.

 

[durhamplumber]

For a slow leak it's probably worth going around each radiator and tighten the bleed valve and it's fitting and the opposite end blanking plug. Then the valve nuts and most importantly the valve spindle nuts. All of these can leak but the water can

Best way of making it worse it you overtighten....and so many modern components are that crappy you make them worse if you touch them

 

[ReganAndCarter]

Must be a tiny weep somewhere if it's not showing up and only need to top up every 3 months. Not worth getting too worried about.

 

[trevorbayliss]

Thanks all. I will check all nuts etc.

 

[Nozzle]

Stick in some really stinky aftershave and close the doors in each room. Whichever roof stinks is where your flashing/drying leak is.

Nozzle

 

[oilhead]

Close off the AAV's in the boiler and the rest of the system if fitted, and see if it still loses pressure after 3 months.

 

[oilboffin]

Grant boilers let you use it once I think but the best thing is not to use it.Bob

 

[chrisw99]

I read in my boiler manual that it is common to have to top the pressure up ever so slightly every few months, as air will naturally bleed out of the internal pump over time.

 

[ianmcd]

Dont use leak sealer it will cause more damage than good

 

[Halfwayowl]

I had the same issues with my system every month the water pressure would drop and i would have top it up, did all checks to try to find leak and never found one. We had a new kitchen 2 years ago and the ceiling was taken down to do the electrics and whilst i was stood watching them one day i had a drop of water hit me on the head, it was a joint leaking but it was so small it must have dried up in the plasterboard and the plumber onsite tightened it up and no problems since, but if the ceiling hadn't been down i would have never found it

 

[trevorbayliss]

I have spoken to the engineer and it seems the expansion vessel needs re-pressurising.