Oil filled radiators are ideal for larger areas such as living rooms or any area needing constant temperature and are set on wheels for portability.They operate by heating oil sealed within the unit, this heat transfers to the outer metal surfaces to heat the surrounding air. The heated air rises to be replaced by cooler air leading to a slow warm air circulation in what is known as a convection cycle. This gives an even, comfortable temperature around the room.Oil filled radiators will not immediatley heat an area you need to run the unit for a while depending the room size. An internal thermal control only calls for power after the oil temperature eventually drops. Many models have a timer and ECO functions for increased user control.Once switched off, the radiator will retain the heat releasing it slowly to give a gradual temperature reduction to the room.