Vokera Compact Se constantly filling

[bennythedip]

Hi all,
called to look at a Vokera compact Se (2005)where there was water constantly filling from the domestic hot water over pressurising the boiler. Checked expansion vessel and ok. I can't see any divertor valve, so am I right in thinking that there is a leak in the heat exchanger between the hot water and central heating or am I missing something obvious as the two circuits appear to be independent ?? Thanks for any replies

 

[bigads28]

That boiler has a duel element or twin pass heat exchanger. Basically the heating and hot water are both heated via the same heat exchanger and there is a hole in it allowing mains into the heating system. Make sure your fill loop isn't passing too!

 

[bennythedip]

The fill loop definitely isn't passing. It's only when the mains supply for hot water is on that the pressure keeps rising. I take it there's no fix apart from a new heat exchanger?? Thanks

 

[Ermintrude]

Possible. Easy check, turn off cold undo inlet and wait for heating to drop

 

[Billy Bob Bob]

Hi all,
called to look at a Vokera compact Se (2005)where there was water constantly filling from the domestic hot water over pressurising the boiler. Checked expansion vessel and ok. I can't see any divertor valve, so am I right in thinking that there is a leak in the heat exchanger between the hot water and central heating or am I missing something obvious as the two circuits appear to be independent ?? Thanks for any replies

if the twin pass hex has failed it probably writes it off

 

[Ermintrude]

Gasman it's a Vokera so a rights way it's in the bin?