Potential Leak - but where???

Mrs7ones

We had a new central heating boiler professionally filled in September, replacing an old back boiler.
All was well until Monday evening when I got in from work to find the heating hadn't come on.
Turns out that the boiler had lost pressure which prevented it from firing up.
Since then, I have had to 're-pressure'??(fill it back up) every morning, evening and night.
I've had the company out (the fitters) and the chap that come said that if the boiler is loosing that much pressure, there has to be a leak somewhere.
Now, we have no visible wet patch anywhere, and the boiler overflow isn't running.............. so where????
The fitter said that as we didn't replace all the old pipe-work (we weren't advised to or didn't even have it suggested), it is possible that an old joint has burst under the pressure of the new system..... and is leaking.
He said he is happy to quote to find and rectify the problem (I bet he is!!).

But surely if we were losing that much water, we would have seen where by now???

Has anyone got any ideas???

TITEASCRAMP

Could it be under the floor? We have a very large void under our house, its about 4' deep. We have heating pipes running under (we have floor boards).
It maybe worth a look.

ormus

its a well know problem when replacing a pressurised system into an old gravity type system. we also replaced a back boiler for a new combi.
under the floor is a likely area for a leak. our house has a huge void underneath. almost a cellar. the original CH pump was under there.
so it was fairly easy to inspect the pipework.

Mrs7ones

We have a cellar too, and the chap looked down there yesterday..... Nothing

Razor

Hi, if the new boiler is a system boiler there is a chance that the coil in the hot water cylinder has split, this would cause pressure loss with no visible damage as the missing water would mix with the domestic hot water, need more details about the system really?

Mrs7ones

Razor wrote: »

Hi, if the new boiler is a system boiler there is a chance that the coil in the hot water cylinder has split, this would cause pressure loss with no visible damage as the missing water would mix with the domestic hot water, need more details about the system really?

It's a Worchester Greenstar (??) Junior combi.

david29dpo

If it's a combi, no tanks to leak so cant be that. You must have a leak somewhere. Is there water coming out the pressure relief valve?

Mrs7ones

david29dpo wrote: »

If it's a combi, no tanks to leak so cant be that. You must have a leak somewhere. Is there water coming out the pressure relief valve?

Sorry for being a bit dim, but would that be the overflow pipe thingie that goes outside??
If so, then no.

I'm thinking that the leak must be being soaked up somewhere as yet, and will reveal itself in time.....??

david29dpo

Mrs7ones wrote: »

Sorry for being a bit dim, but would that be the overflow pipe thingie that goes outside??
If so, then no.

I'm thinking that the leak must be being soaked up somewhere as yet, and will reveal itself in time.....??

Yes. To lose pressure so quickly you must have a far old leak somewhere.

Mrs7ones

so how much water do you think we're loosing and how long would you expect it to take to show damage?

david29dpo

If it's loosing full pressure so quickly it could be a gallon or so each time. The water has to be going some where. You may need to start lifting floorboards to check ALL pipes and connections.