Terminology
[+]⇒ Since 2025, ISO/TC 341 has had a working group on "Terminology," which aims to define all district heating terms in a uniform international manner.
Contributors are welcome; please contact us if you are interested.
Transfer Medium
[+]⇒ Since 2025, ISO/TC 341 has had a working group on the topic of "Quality of heat transfer medium," which focuses on water quality within the district heating network.
We are looking for experts for this purpose; please contact us if you are interested.
Long-distance Heating Network
[+]⇒ Since 2025, ISO/TC 341 has had a working group on the topic of "Long-distance Heating Networks." This group focuses on transmission lines with lengths of 20 to 150 km and very large diameters (D > 1200 mm).
If you are interested in participating in this group, please contact us.
Future projects in the ISO
A number of projects are currently under discussion.
The aforementioned projects have not yet been scheduled.
Design requirements for network systems
[+]⇒ ISO/TC 341 will soon be setting up a working group under project number ISO 25618-1 to deal with Design requirements for district heating and cooling network systems — Part 1: General requirements
We are looking for experts for this purpose; please contact us if you are interested.
Substations components
[+]⇒ ISO/TC 341 will soon establish a working group under project number ISO 25194 to deal with Technical requirements for substations components used in urban heating and cooling supply network. This group will focus on substations, transfer stations, and their components.
We are looking for experts for this purpose; please contact us if you are interested.
Completed projects in the ISO
No standards have yet been drawn up in ISO/TC 341, but it is anticipated that they will be completed within the next few months.
last update: 01.07.2026-MSt






