Pressure Loss - Loose end please help!!!

[lukesaw]

Hi Everyone,

I moved into a new flat about 18 months ago. After a few months the boiler pressure started dropping to 0 daily which I just repressurized as needed.

The boiler eventually stopped working all together (old) so had a new BAXI combi boiler put in.

Since day one had the same problem - pressure going from 1 - 0 BAR which I would top up daily.

There have been no signs of leaks which is strange as has been going on for over a year. Have bled all radiators and same thing happening.

The strange thing is when I switch my boiler off and repressurize with just cold water in the system, the pressure stays put.

Also I get home from work and the pressure is 0 - repressurize have a shower etc, and the pressure stays put until the morning at 1 BAR (i.e. over about 8 hours). However when I come home form work when no heating has been used during the day the boiler pressure is at 0.

Both British Gas and BAXI havent a clue what is going on.

Any advice?

Thanks

 

[Howsie]

Neither of them had any suggestions? What's the world coming to. You could be losing water in a manner of ways, if the boiler is new, I'd get them back to fault find it even if it's not the boiler.

 

[Riley]

Agreed my betting would be increasing pressure from somewhere be it an old filling loop or something similar

 

[Unregistered]

Hi Riley, what do you mean by this? Sorry i'm a real amateur!

 

[Riley]

You either have a leak somewhere that possibly only becomes apparent when the system is hot and expands. Or there is a possibility that your previous boiler had an external filling loop which may still be in place but is letting by causing the pressure in your heating system to gradually increase to a point where the safety devices kick in and your boiler releases pressure to outside

 

[Howsie]

I'm confused on the filling loop point? How did you come to that conclusion?

 

[Riley]

As above mate I have had two cases where an old filling loop is left in situ ( often hidden behind a kitchen unit) and they have begun to let by meaning that the pressure Rises gradually until the PRV of the boiler does its job more often than not this happens at night when the usage in the area is less and pressure is higher so come the morning the PRV has lowered the pressure again
It might not be of course in this case but I just wanted to throw it into the mix

 

[Howsie]

The PRV should bring it back down to 3 bar, unless it's sticking of course...

 

[Riley]

Granted yes these ones have been older boilers so it couldve been a sticking PRV :smile:

 

[GasmanxxxR1]

Did BG install the new boiler? If you kick up enough fuss they will sort it out, even if it means repiping

 

[lukesaw]

There is also some wetness on one of the pipes below the boiler which looks like its formed a small puddle under the floor board - however as this has been going on daily for about 16 months surely there would have been a more sizeable leak by now?

All the pipework goes under the laminate floorign the into concrete so not really able to go digging up.

If I have it all repiped within the interior of the flat would that solve things?

Had a friend put the boiler in but as it has the same problem as the previous boiler it must be something that was consistent accross the two?

Also the pressure doesnt seem to increase above the point I put it at (1 bar). I am confused why it doesnt drop at all overnight over like 8 hours but does during the day over 10 hours when i am not at home and no heating/hot water is being use?

 

[Howsie]

If your friend fits boilers then I'd get him around to have a look at what's going on. I wouldn't leave a property which had an ongoing leak...

 

[Riley]

Absolutely you shouldn't leave a customer with a leak whether it is existing or not I hope he was gas safe

 

[Riley]

There is also some wetness on one of the pipes below the boiler which looks like its formed a small puddle under the floor board - however as this has been going on daily for about 16 months surely there would have been a more sizeable leak by now?

All the pipework goes under the laminate floorign the into concrete so not really able to go digging up.

If I have it all repiped within the interior of the flat would that solve things?

Had a friend put the boiler in but as it has the same problem as the previous boiler it must be something that was consistent accross the two?

Also the pressure doesnt seem to increase above the point I put it at (1 bar). I am confused why it doesnt drop at all overnight over like 8 hours but does during the day over 10 hours when i am not at home and no heating/hot water is being use?

I assume it is probably A leak that only becomes apparent during the heating and expansion process

 

[lukesaw]

Why would you think the pressure doesn't drop during the evening and overnight at all, but drops to zero during the day when I am out and no heating/hot water is used?

 

[Riley]

I have said it three times now it is quite likely that when your pipework heats and expands it is opening up a hole then when it cools down it closes the gap again

 

[Howsie]

Or the other way around. It's also quite possible that it's continually dropping and it's more noticeable when you come home from work.

A little like watching bamboo growing.

 

[Riley]

You can guarantee it pretty much always will do it when you're not looking :smile: