vokera linea 24 losing pressure

[vonleeds]

Help !!! Our boiler drops in pressure over a period of 3-4 days it will drop from 1.5 bar to almost zero so we are regularly refilling the boiler. There is no water coming out of the outlet outside. also not sure if its connected to the boiler pressure dropping the temerature fluctuates but only in the shower (we have a mixer tap). we have tested running the water through the all taps and the temperature remains constant. (including when it is run through the bath mixer tap) when it is flicked to the shower approx 1-2mins the water will go cold and the temaperture gage on the boiler drops. after testing this a number of times on the shower, with the temperature dropping regularly. it suddenly remained constant for well over 5mins. and only when cold water was added did it begin to fluctuate again and the temparature on the boiler drop. we have had a service carried out, new thermistors fitted. but nothing seems to solve the problem, any suggestions welcomed before we go to a lot of expenses trying to trace a leak in the pipes.

 

[cross thread]

get the expansion vessel checked

 

[biscuit77]

If all your radiators and radiator valves are dry and there is no leaks around your boiler and you're sure there's no water coming out off the pressure relief pipe, then get a gas safe engineer to check the main heat exchanger on your boiler, vokera boilers off the type you have are famous for internalleaks on the main heat exchanger.

 

[vonleeds]

Thanks both for your advice much appreciated, someone had said heat exchanger to us before but when last boiler man came round we asked about that & he said it would and be more eratic and on all taps, but he was also wanting to start ripping up floorboards to find a leak saying it would cost thousands.! so wasnt sure i believed him ! would the heat exchanger also cause pressure to drop ? would a leak cause pressure to drop more rapidly, definately no leaks on any radiators/valves we have checked pipes under house for leaks on ground floor cant find anything & no damp patches from upstairs.we have insurance plan on boiler/radiators that doesnt cover pipework which is why i think they are trying to suggest a leak.

 

[biscuit77]

Get them back out to check the heat exchanger. If when they take the combustion chamber cover off there is any staining on the side insulation panels or the heat exchanger has green staining(normally at the sides of it),it needs changed. Don't be afraid to ask them to show you the inside off the boiler.

 

[vonleeds]

will do, thanks for your help will let you know how we get on !.

 

[biscuit77]

No problem.