DIN 4757-1:1980-11

1 Scope
2 Preconditions
3 Concepts
4 Classification of solar heating plants
5 Safety requirements relating to materials, type and
      manufacture
      5.1 Materials
      5.2 Applicability of the materials
      5.3 Solar collectors
      5.4 Pipelines
      5.5 Heat accumulators
      5.6 Heat exchangers
      5.7 Expansion vessels
6 Equipment
      6.1 Safety devices for open plants in accordance
             with sub-clause 4.1
      6.2 Safety devices for closed plants in accordance
             with sub-clause 4.2
      6.3 Further equipment
7 Heat transfer medium
8 Installation
9 Testing
10 Operating instructions

Applies to open and closed solar heating plants with natural circulation (thermosiphon or gravity circulation) and with forced circulation in accordance with sub-clause 4.1 and sub-clause 4.2. The hear transfer media used include water, water with the addition of antifreezes and synthetic heat transfer media which are mixed with water, and which have a boiling point of the mixture situation above the boiling point of the water. This mixture must be non-combustible. DIN 4757 Part 2 applies to solar heating plants operating on organic heat transfer media.