There is a tendency in shops is to sell stoves which are too small for their purpose. This means that your stove will not last so long because you have to run it to its maximum capacity constantly to get the heat output you require.
All wood burning and multi fuel stoves have a kilowatt rating. That is the approximate maximum temperature the casting is able to cope with. It has nothing to do with how warm the heat production is. The heat production comes from the fuel used, ie the fire you create in the stove.
For example, if you require 3 to 5 kilowatts to heat your room then the correct course is to buy a stove with a slightly larger kilowatt rating and light a fire to suit - your stove will then last you much longer. The best idea is to buy the stove which looks aesthetically pleasing in your fireplace. This is what adds the value to your home.
The method used to calculate the kw or heat production required to heat the room is Room Height in meters * Room Width in meters * Room Depth in meters, all divided by 14. This gives the kilowatt needed to keep your room heated. It does not give the kw rating of the stove required nor does this calculation consider insulation or drafts or heat loss up a large chimney or a vast range of other variables. It is a very, very rough guide and the actual sum which gives the killowatt required is based on an external temperature of 5 degrees above freezing, where many people would not be really requiring much heat from their stove.
As you can see, the sum to calculate the heat required is not exact but rather a rough estimate.
If you require assistance on this please phone the Country Kiln Team on 01560 438966 with the measurements of your room.