Sunday was no ordinary day for Riley.

The Year 10 Ballarat High School student was visiting his grandmother in Brown Hill when he heard a smoke alarm nearby.

Realising an 80-year-old man was inside the burning kitchen, the 15-year-old ran into the home - wearing a singlet and shorts - and tried to convince the confused elderly man to get out.

Using his singlet to cover the man's nose and mouth, Riley guided him outside, where he later collapsed and sadly could not be revived.

The teen hero says the memory of his 3 year old brother  - who died in a 2011 train accident - went through his head when he saw the fire.