From reading other threads I think I alredy know the answer but I am just checking before I pay out!
Vokera, linea 24 aprox 8 years old.
1. central heating pressure is dropping when central heating is not on
2. I have the preheat quite high because we use a mixer shower - when the central heating is not on and we use hot water it heats the upstairs radiators (unit is upstairs and upstairs rads are first off). also when unit maintains the pre heat it again heats the upstairs rads first.
3. Gas usage as increased
Do you think it is the diverter that needs to be changed i.e. diaphram spliit?
The heat exchanger was changed 2 years ago.
PS. I am not ofay with these things so please be kind if I have got it wrong
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