I have recently re pressurised the expansion vessel to 12psi having isolated and drained the boiler. The vessel holds it's pressure, valve is dry and no signs of water from prv / external drain pipe. No error code on boiler.
Boiler pressure restored to 1bar cold, water clean.
On start up. the boiler will heat correctly to lower temperatures (set using temp dial on boiler), both HW & CH (60 Deg os so).
However, when the CH temperature dial is set to Max (HW dial left set to Min), the stystem will heat to around 85 Deg but the boiler then 'runs hot' - the boiler coming on every 20-30 seconds and running for about the same, maintaining a temp of around 85 Deg? Boiler pressure will increase to around 2 bar.
Turning the CH temp control from max to min does not reduce the running temp down from around 85 degrees?
Any suggestions much appreciated.
Boiler pressure restored to 1bar cold, water clean.
On start up. the boiler will heat correctly to lower temperatures (set using temp dial on boiler), both HW & CH (60 Deg os so).
However, when the CH temperature dial is set to Max (HW dial left set to Min), the stystem will heat to around 85 Deg but the boiler then 'runs hot' - the boiler coming on every 20-30 seconds and running for about the same, maintaining a temp of around 85 Deg? Boiler pressure will increase to around 2 bar.
Turning the CH temp control from max to min does not reduce the running temp down from around 85 degrees?
Any suggestions much appreciated.