Vokera Linea 726 Pressure problem.

[Stinkwheel]

Hi Folks,

Im sure this is a really obvious solution but My expertise is electronics not central heating.............

My boiler works fine but whilst not actually lit is loosing pressure, if left overnight it looses enough to lockout and flash the low pressure code at me, it can be made to work by opening the filling loop and getting it pressured up again, then it starts to tail off again from there.

Anyone any ideas please?

 

[scatmanjohn]

Is there any signs of water leaks anywhere on the system.
Check the pressure relief pipe outside to see if it is dripping.
The main heat exchangers on these boilers are prone to leaking, if there is no signs of any water anywhere (after a thorough check) suspect the heat exchanger.

 

[Stinkwheel]

can find no signs of leakage, i thought probably expansion vessel at first but that had plenty of charge and no water was released at the valve so diaphragm ok, pumped back up to recommended pressure.

Not come accross the heat exhanger problem before, any sure fire ways to identify that as being at fault?

 

[ChrisR]

You could close the boiler isolating valves and leave it overnight. They might leak a little though the stems as a result, depending how old the boiler is, but they usually seem to stop again after a day or two.

Signs of leaks are often evident inside the boiler.

 

[Stinkwheel]

there is no ;eaks inside the boiler casing, have checked it all out, filling loop disconnected (shut and pipe removed) and its still looses pressure. Im bemused its acting just like expansion vessel. Even goes a bit too high when its refilled like it would but thats not got water at valve and holds its pressure fine???

 

[scatmanjohn]

When you say there are no leaks inside the boiler case do you mean inside the combustion chamber? If the leak is on the heat exchanger you won't see any water because as it leaks out it either dries out straight away or can soak into the insulation panels and be dried out when the boiler fires.
The giveaway is staining on the panels and white crusty deposits in the bottom of the combustion chamber.

 

[Nige F]

Stinkwheel from Bikersweb or just a coincidence

 

[Stinkwheel]

I will check what you are saying about leaks again.

Nige F I am a biker and i do hang about various web bike places but not on bikersweb mate