When the boiler calls for heating/hot water it doesn't activate the burner, no lockout, oil ok. when you ask for heating the circulation pump runs. Been advised it is the PCB, but not able to look yet, does this sound feesable

John, July 2008

Souns like the PCB, But Could be the Thermistor, you can get both items on a single part number, before ordering open the control panel on the RDB Burner and ensure that when heat is calling you have lost a 230v supply at the burner, part is about £40

Boiler Repairman, May 2009