how can i fis oil filled radiator power light on but no heat?

Hi,
If it lights up but doesn't heat up, then the temperature sensing cut-out switch is probably dead.
The switch is constantly heating up & then cutting out in order to prevent the heater from overheating. As a result of this process they do wear out.
If you are DIY able & safe you could replace the damaged part. If you are not, I would suggest that it's no use to you as it will be cheaper to replace it than pay to have it repaired.
Try Freecycling it.!!

Dr_Bez
November 2009