HNTAS: Existing heat networks - draft overview of technical specifications

This draft document provides an overview of the series of technical specifications applicable to the elements within an existing (operational) heat network. It sets out:

• how these requirements are separated into distinct milestones
• how technical requirements are to be achieved and demonstrated

It is for use by:

• heat network operators
• organisations within the heat network supply chain

This technical specification overview for existing heat networks corresponds with the HNTAS: Existing heat networks - draft overview of assessment procedures.

Next steps

We will be requesting feedback on the information in these documents. We will run a change management process in parallel with the HNTAS technical standards consultation which closes on 15 April 2026.

We will make final versions of these documents available before the scheme starts.