The thermal yield of electric heating products and the calculation of the heat requirement to ensure the correct heating of your rooms depend on 3 basic parameters:
1) The size of the room in square meters
2) The degree of thermal insulation of the room
3) The average outdoor temperature of the Geographical area of the house
Clearly there are also other factors that can influence the choice of the most appropriate product such as, for example, the exposure of the room to the north or south, its intended use (domestic or commercial) or subjective needs of ambient temperatures higher than the average.
However, this guide provides an indication for the calculation of the ideal average heat requirement to ensure a correct heating level with a responsible consumption of energy.
PREMISE
Assume as a matter of fact that the house we are talking about has a degree of normal thermal insulation (where for "normal" we mean a house built between the years 70 and 80 and then probably with an ENERGY CLASS between the G and the E ) and that the ceiling height is between 2.7 and 3.0 meters, not higher.
ITALIAN GEOGRAPHIC AREAS
We have identified 4 different geographical areas:
PURPLE: VERY COLD ZONES: areas where the average winter temperatures are between -15 °C and 0 °C
BLUE: COLD AREAS: areas where the average winter temperatures are between -5 °C and + 5 °C
YELLOW: MYTH ZONES: areas where the average winter temperatures are between 5 °C and 12 °C
GREEN: WARM ZONES: areas where the average winter temperatures are between 12 °C and 15 °C
SPECIFIC POWER
For each geographic area it is possible to identify the minimum recommended specific power according to the intended use of the room to be heated:
- Bedrooms, kitchens, corridors
VERY COLD GEOGRAPHIC AREAS> minimum specific power = 100W / sqm
COLD GEOGRAPHIC AREAS> minimum specific power = 90W / sqm
GEOGRAPHICAL AREAS MYTHS> minimum specific power = 80W / sqm
WARM GEOGRAPHIC AREAS> minimum specific power = 70W / sqm
- Dining rooms, living rooms, bathrooms
VERY COLD GEOGRAPHIC AREAS> minimum specific power = 120W / sqm
COLD GEOGRAPHIC AREAS> minimum specific power = 100W / sqm
GEOGRAPHICAL AREAS MYTHS> minimum specific power = 90W / sqm
WARM GEOGRAPHIC AREAS> minimum specific power = 80W / sqm
CHOICE OF THE PRODUCT MORE SUITABLE TO YOUR NEEDS
To choose the product that best suits your needs, simply multiply the specific power (obtained for the type of room and the geographical area) for the size of the room.
Example: It is necessary to heat a 10 m2 bedroom in a house in Naples.
1) The size of the room is 10m2
2) The identified geographical area is WARM
3) The minimum recommended specific power for a bedroom in a hot area is 70W / m2
4) The minimum recommended power is 70 x 10 = 700W so all models with a power equal to or higher than this value will be fine (for example the 750W KLIMA 7 or the 1000W SIRIO 10)
- Note 1: in the case of very old houses and / or a very low level of thermal insulation, it is advisable to increase the specific power by 20%.
- Note 2: in the case of homes built after 1990 and / or with thermal insulation that meets the class C or D certification requirements, it is possible to reduce the specific power by 20%.
- Note 3: in the case of homes built after 2005 and with thermal insulation that corresponds to the class A or B certification requirements, it is possible to reduce the specific power of 40%.