when the central heating comes on there is a loud bang. its sometimes the second or third time the central heating comes on, its really loud and frightening i have bled the radiators and they seem ok. my boiler is an ideal icos and only 3 years old. how can i resolve this issue.
Horrible boiler, sounds like 'explosive ignition' - have it checked out by an engineer and make sure he checks the burner and electrodes as Ideal have safety notices with regards to their electrodes on some ICOS/ISAR models.... also have the combustion checked to make sure the gas mixture is ok, could be the spark gap is poor or spark itself.... have it checked