Hi
I have a pressurised central heating system based on a Trianco Trader
90 boiler with a monoflame burner which is controlled by a Honeywell ST6200A unit. Occasionally the boiler will fire up during times when the heating and hot water are set to off at the controller. I thought that this might be normal during the winter when it would be important to prevent the boiler from freezing but not during the summer!Can anyone advise me as to what the problem might be? Do I need a new controller perhaps?
TIA