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Domestic solar water heaters
Certification manual
Certification Manual NF
Certification reference standard

Scope of the programme

This program applies to domestic solar water heaters with forced circulation with or without supplementary heating built into the storage tank which can be tested according to the NF EN 12976 or 12977. Domestic solar water heaters with a storage tank of more than 500 litres are not included in this scope.
Water heaters implementing provisions for mitigating the risk of the development of legionella bacteria.
Products included in NF441 programme:
Classical domestic solar water heaters “Split systems”
Note: Thermal performances determination for mixed auxiliary heat systems is performed by two sets of tests, each covering the operation of the system with only one of the two types of auxiliaries.
Classical domestic solar water heaters “Monoblocs”

Certified characteristics 

The main certified characteristics and performances are calculated / tested without auxiliary production.
Characteristics of the system: 
  • Ac: Solar capting area in m2,
  • Uc: Themal loss coefficient of the collector in W/ m2..K,
  • Us: Themal loss coefficient of the storage in W/K, 
  • Cs: Thermal capacity of the storage in MJ/K,
  • Energy efficiency of the system in %,
  • Energy production of the systems in kWh/year.
This production will be given for:
5 different meteorological climates:
  • Stockholm (59.6° N),
  • Würzburg (49.5° N)
  • Davos (46.8° N)
  • Nice (43.6° N)
  • Athens (38.0° N)
5 different daily drawing loads:
  • 80 litres,
  • 110 litres,
  • 140 litres,
  • 170 litres,
  • 200 litres.
Note: The thermal characteristics of the range variants of solar domestic hot water heaters are estimated by calculation. In order to calculate and test the individual products, a complete data sheet must be supplied.
These certified characteristics are evaluated under the responsibility of EUROVENT CERTITA CERTIFICATION.
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