Boiler in kitchen down stairs, hot water tank, pump and diverter value up stairs, water tank and CHS tank in loft.
When all radiators are open, system works as normal.
When even one radiator is turned down (doesn't have to be off), boiler cuts out giving "Over pressure" error code and will constantly give that error until all radiators are open again.
What would be the first thing to check?
When all radiators are open, system works as normal.
When even one radiator is turned down (doesn't have to be off), boiler cuts out giving "Over pressure" error code and will constantly give that error until all radiators are open again.
What would be the first thing to check?