How to calculate the BTU power required for an air conditioner

Here are some simple steps to follow to calculate the BTU needed to cool our environment. It is highly recommended to perform a step at a time and write down the calculations that at each step will come out!
Step 1: Compute the area of ​​the rooms that we want to cool. To do this we calculate for each room the length and the width (the height of the room in this calculation we do not need). Then multiply the width to the length thus obtaining the square area of ​​this room. Now we add the various areas of the rooms previously taken into account. Since that for every square meter we need around 350 350 BTU multiply the sum previously calculated.
Step 2: We calculate also the sizes of the windows (height by width) present in the rooms that we want to cool. Multiply the square feet to 900 BTU if the window faces south and for 170 if it is exposed to the north. Recall that the south-facing windows are those that let in more light during the day.
Step 3: calculate the number of people who are usually present in the house (in our example) or in our environment that we want to cool. For each person considered 400 BTU.
Step 4: Let's look at our lights. Note the number of watts for each bulb and multiply it by 4.25 BTU. For example, a 100 watt bulb should generate 425 BTU.
Step 5: Check if you have any electrical equipment or machinery that will be running in the rooms to be cooled. Check the maximum power of the moltiplicartela and then to 3.15. Although the maximum power will almost never reached by the appliance is always a good idea to have an air conditioner that also meets these occurrences.
Step 6: We add the BTU calculated at each previous step. We so easily calculated power in BTU needed to cool our room!
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