Oil filled radiators usually have a product known as diathermic oil. This is a special type of oil which is uniquely well suited to be used inside electric radiators.
There are two reasons why it is so well suited:
Diathermic oil is known to be able to hold an impressive amount of heat before it temperature starts to rise. This is easiest to understand by acknowledging that water boils at 100 C, but if you add antifreeze to it the boiling point rises to 106 C. In effect, it can hold the heat better.
Diathermic oil works on this principle.
Diathermic oil takes a long time to boil; it needs to reach a temperature of 300 C before it starts! This is particularly relevant as any liquid which reaches boiling point turns to vapour. If this is inside a sealed heating unit the vapour will create additional pressure and could cause an explosion. This is not an issue with diathermic oil as its boiling point is so high.
These two properties make this oil perfectly suited for inclusion in your electric heater.re is no need for pressure release systems or complicated systems; the diathermic oil simply cannot get hot enough to boil inside a radiator.
The Additional benefit
An added bonus of this oil inside your radiator is that it can be switched off but will still emit heat for an impressive amount of time. This is because it holds its heat so well; it disperses slowly. You can, therefore, save electricity costs by using a diathermic oil radiator!