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The confusion here seems to be that the refrigeration capacity of the air conditioner in your living room (LR), 12600 BTU, has nothing to do with how much energy is required to move that much heat. The amount of energy needed to move the heat depends on what temperature difference the evaporator (room air temperature) and condenser (outside air temperature) coils are operating at, and the Coefficient of Performance (COP) of your particular AC (air conditioner) unit.

Using, as an example, +5 C as the living room or LR temperature and +30 C as the outside air temperature, the maximum Carnot cycle COP is only 278 / (303-278) = 11.12 = Q/W, where Q is the amount of heat moved and W is the work required to move it between those two temperatures using the Carnot cycle. A real AC unit will have a much lower COP, closer to 3 rather than 11. But, this is important, notice that as long as the COP is greater than unity, it will always take less energy to move a certain quantity of heat (BTUs) than the energy (joules) represented by that heat.

So, if your 12600 BTU/hr AC has a COP of 3.0, it will typically require 12,600/3 = 4,200 BTU/hr to operate it. This is about 1231 watts, consistent with your 120 VAC (volts alternating current) times 15 A (amperes) current or a maximum load of 1800 watts.

More information can be read here: http://www.alephzero.co.uk/ref/practcop.…
Source(s):
http://www.alephzero.co.uk/ref/practcop.…

11 years ago. Rating: 0
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since there are 3412BThU's in 1KWhr it is easy to work out multiply 1.5 X 3412=  5118 BThU's

11 years ago. Rating: 0
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