Frigories to BTU converter
One frigorie per hour is 3.97 BTU/h. Here are the rest.
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European spec sheets quote capacity in kW, not in BTU.
Where each number comes from Conversion constants are exact; densities and coverage rates come from cited sources; everything else is an assumption you can change. Methodology · Sources and updates
How to use it
- Enter the frigories quoted by the shop or printed on an older unit.
- Read the BTU/h: that is the figure you will search international catalogues with.
- Compare it with the nearest commercial step, which almost never matches exactly.
- If you also need the kW from the spec sheet, they are in the same table.
How it is calculated
You need this conversion when the number you have is the one Spanish and Latin American shops use and the number you need is the one international catalogues use. It comes up most often when replacing an old unit: the plate says 2,500 frigories and every spec sheet online talks in BTU.
It is also useful for checking the opposite of what it looks like: whether the unit you are being offered really matches the one you had, or whether you are being moved up a size.
The conversion, exactly
All three units measure the same thing, energy per unit of time, and only the scale changes: the watt belongs to the SI, the BTU/h to English-speaking markets and the frigorie per hour to Spain and Latin America. The ton of refrigeration, used on larger equipment, is 12,000 BTU/h by definition.
Worked example
A 3,000 frigorie unit:
- In watts: 3,000 x 1.163 = 3,489 W
- In BTU/h: 3,489 x 3.412 = 11,905 BTU/h
- Commercial size: 12,000 BTU/h
Which is why 3,000-frigorie units are sold as 12,000 BTU: the difference is under 1 % and the round number sells better.
Good to know
- 3,000 frigories is not exactly 12,000 BTU. It is 11,905, 0.8 % less. Shops round up because round numbers sell, but comparing two units over that 0.8 % is comparing noise.
- A frigorie is power, not energy. One frigorie per hour is one kilocalorie per hour. When someone says "this unit has 3,000 frigories" they mean per hour, even if they swallow the last two words.
- An old unit does not deliver what its plate says. The conversion is exact; the machine, after fifteen years, is not. If you are replacing it, size for the room, not for the plate.
Frequently asked questions
How many BTU is 3,000 frigories?
11,905 BTU/h, which is commercially rounded to 12,000 BTU/h. The exact conversion is multiplying frigories by 3.96832.
How many BTU is one frigorie?
3.96832 BTU/h. It is an exact constant, because both the frigorie (1 kcal/h = 1.163 W) and the BTU/h (0.29307107 W) are precisely defined.
Why do Spanish-speaking markets use frigories?
Because a frigorie is simply a kilocalorie per hour, a traditional metric unit that settled into the market before equipment was labelled in kW or BTU.
Is a frigorie the same as a negative calorie?
That is the colloquial explanation, but technically a frigorie per hour is just a kilocalorie per hour of cooling output.