Boiler Pressure drops cant find leak

Lyris83

Hi there

We are a couple renting a 3 bed house and in the past month have had a new bexi combi boiler fitted after issues with the old one. After about 2 weeks we noticed the pressure would drop to 0 overnight. I checked all radiators and visible pipes and no sign of a leak. This has now gotten worse to the point that yesterday we had to top it up 6 times. I am on twice today already. We called out the plumber the landlord uses who fits the boiler and does all the general related issues at the address.

He again checked all radiators, inside the boiler, the PRV and followed the small amount of pipework that isnt visible around to see if theres any noticable stains / damp etc. This is a drop system and there are no pipes under the floor at ground floor level and only a small amount on the top floor. The entire house only has 7 radiators. He is totally flabberghasted as he said a pressure drop of that much would be a significant leak that should be showing somewhere. At a loss, he left with no real ideas of what to do next.

Last night and today i have been meticulous in checking pipes again, tying tissue around them to come back to and check for wetness and even pulling up bits of carpet around pipework to check where it goes and check the corresponding parts of the ceiling downstairs. I am still at a total loss.

I am a total laywoman but have a basic understanding of the system from all my research trying to figure out what is going on.

Does anyone have any suggestions? I cant live like this with heating and hot water going off this many times and its really upsetting me. I know this is technically the landlords responsibility however it is unlikely he will move fast to get this sorted from experience and im terrified there is a huge leak somewhere that will sooner or later bite us all. If i can find it, i can at least point the plumber in its direction to fix it.

Thanks for any replies

MrBrindle

We had this issue with a recently bought house, although not a pressure drop like that. I was also terrified of a huge leak somewhere, being an anxious person didn't help.

Did he check the expansion vessel at all, our problem was one inside the boiler itself. The plumber re inflated the rubber thing inside it, and seemed to sort it out. How that controls the pressure I don't know.

southcoastrgi

Tie a plastic bag around the copper pipe that goes from the boiler to the outside & see if you get water in it ?
The only other way is to isolate the boiler & leave it for 24 hours to see if the pressure drops, if it does it's the boiler if it doesn't it's the heating system

Owain_Moneysaver

For a drop to 0 overnight I'd suspect the PRV or the expansion vessel, as above.

A slow leak (although it doesn't sound like you've got one) might evaporate without leaving staining - plumber could put some fluorescein tracer dye into the radiator circuit which will be much more visible than water where it leaks.

Lyris83

Thanks for all your responses.

We have now found the leak... in thanks due to it being sizeable and has started to creep out of what appears to be the wall and spreadimg across the floor in the hallway.

Plumber cant get out until monday afternoon.