I was talking about oil filled no fuelled, the oil stores some of the heat, so although the heater is switching on/off with a mark/space ratio, it feels as if it is always heating.
Although a fan heater will heat the room, we feel cold as soon as the fan turns off, heaters are better if we can't tell if on or off, I find that room temperature is really odd, I am sitting now in a room showing 17.7ºC and I am feeling comfortable, but same in the evening I feel cold.
Also the reverse can be true, turn on an uncontrolled heater, and one can sit in a room at 32ºC and feel just cosy, but same temperature in summer, and the sweat would be rolling off one, and one gets out the AC, only after leaving the room and returning do you realised how hot it is.
I know some is down to radiant heat, I know 19ºC was ample when we had tungsten lamps, but with LED lamps looking at more like 22ºC at least in the evening, but more to the point here, is all the rooms in the house except for living room can drop to 15ºC without it feeling cold, as long as the living room is warm.
But then the question is if the central heating is efficient heating just one room? We had a 20 kW oil boiler non modulating heating two at best 2 kW radiators, plus the DHW, the radiator TRV valves are likely reducing the radiators output so likely the percentage of heat going into pipes and so rest of house, and also out of the flue, means the boiler is not very efficient at such a low output.
With a gas boiler I could read gas meter and see what it uses, but with oil measuring height of oil in tank is not accurate enough, all I can do is measure run time.
So 16 hours at 750 watt = 0.6 hours run time for the boiler, once fired up, boiler tends to run even height of summer 20 minutes, or 0.3 hours and it would fire up more than twice a day. For a thermal circulations to start the radiators need to be warms for maybe ½ an hour, but oil is still cheaper than electric.
But considering all of this, it seems likely Autumn and Spring the oil filled radiator may work out cheaper. Heart of Winter no option central heating required as want some heat in all rooms, but Autumn and Spring when not all that cold outside, the oil filled radiator may be a better idea, specially if between the two easy chairs, so heating occupants and room not a cold outside wall, who ever thought a good place for radiators is under a window I don't know.
My hope is someone else has done this before, and I can learn from them.
