Kalkulator BTU
The detailed guide below is currently available in English.
The rule behind the number
Cooling estimates start from roughly 20 BTU per hour for each square foot of floor space with an 8-foot ceiling. Taller ceilings add air volume, so the base scales with ceiling height. A sunny room works the unit about 10% harder, a heavily shaded one about 10% less, and kitchens get a flat 600 BTU bump for appliance heat. The result is rounded to the nearest 100 BTU, close to how units are actually rated.
Choosing between two sizes
Real air conditioners come in fixed capacities, so pick the unit at or just above the estimate. An undersized unit runs constantly on hot afternoons; an oversized one cools so quickly that it shuts off before removing humidity, leaving rooms clammy. When your estimate sits between two models, the smaller one usually feels more comfortable.
Częste pytania
Does room height really change the BTU needed?
Yes, modestly. The 20 BTU per square foot rule assumes an 8-foot ceiling. A 10-foot ceiling holds 25% more air, so the estimate scales the base load upward by the same proportion.
What is a ton of cooling?
One ton equals 12,000 BTU per hour, a figure inherited from the ice-melting capacity of early refrigeration. The tonnage row converts the estimate so you can compare window units and central systems rated in tons.