–How to calculate the air conditioning power for a given surface area?
When it comes to buying a domestic air conditioning system, the same question always arises: What power is the right one? How many frigories or watts do I need per square metre? Depending on the answer, the investment and performance will vary depending on the power of the air conditioning system you install.
Choose the equipment that optimises performance
The first thing to consider is that you don't always have to buy the most powerful equipment, but look for the one that best suits your needs. If you make the wrong choice, you may have excessive power consumption or, worse still, you may not get the right performance and waste energy.
Nowadays, most air conditioners incorporate Inverter technology, which is essential for reducing electricity consumption and achieving more efficient air conditioning.
When assessing the energy consumption of an air conditioner, the most important thing is the classification of the machines. It is always advisable to opt for equipment with A, B or C efficiency (until 2022 classified as A+, A++ or A+++).
Calculating the cooling capacity or watts per m2
Both the cooling capacity and the watt are the units of measurement used in air-conditioning systems, both by manufacturers and installers.
As a general measure, the calculation of 100 frigories per square metre of the room is usually used. For example, a room of 27 m2 would need an equipment of 2700 frigories.
1m2 = 100 frigories
Calculating the thermal power in watts per m2
The watt (W) indicates the thermal power required to air-condition the room. It is necessary to distinguish thermal power from electrical power, as both are measured in watts. It will depend above all on the energy efficiency of the equipment, but the information they give us is totally different: on the one hand, the thermal power gives us information about the power in cold or heat that the equipment will provide us with, and on the other hand, the electrical power gives us information about the consumption that the equipment will have in operation in both cold and heat.
If you want to know what power your installation would need in watts, you only have to multiply the value in frigories by 1,163.
1 frig = 1,163 watts/hour
Following the previous example, an installation that requires 2700 frigories would need a unit with a thermal power of 3140 watts.
In the case that you know the power in watts, but you want to know how many frigories it is equivalent to, you would only have to multiply the power in frigories by 0.86.
1 watt = 0,86 frigories/hour
You will often find that thermal power is expressed in kilowatts (kW). 1 kilowatt equals 1000 watts. Thus, an air conditioning installation requiring 2322 W would be equivalent to 2.3 kW.
Power required for your air conditioner according to room size
Below is a table showing the average power required for certain rooms according to their size in m2:
IMG BODY 3
Bear in mind that the final calculation is influenced by many other factors, so we advise you to always consult a professional air conditioning installer to find out what power your equipment needs. By analysing the space, he will make the most accurate calculation so that your equipment is the most efficient and consumes exactly what you need.
Factors that influence the calculation of the power of the air conditioning installation
To calculate the power that your installation needs, in addition to the surface area, the installer will take into consideration:
- The environmental conditions of humidity and temperature.
- The thermal insulation of the home. The better the insulation, the lower the power required by your equipment.
- The size of the windows or balconies and the quality of the glass.
- The orientation of the house. The more direct sunlight it receives, the higher the cooling power and the lower the heating power required to keep the space at the optimum temperature.
- The number of electronic equipment connected in the room, as these can add heat to the environment.
In addition, it is necessary to take into account that it is not the same to air-condition a 70 square metre flat as it is to air-condition commercial premises or an office. The needs and thermal conditions will be very different, so additional factors will have to be taken into account.
The Hitachi residential air conditioning range
Hitachi air conditioners are available in a wide range of power ratings, from 1.8 to 7 kW, to suit all types of rooms.
Here you can see all the home air conditioning units available.
by Hitachi Cooling & Heating
