21/05/2026
Delta T: the small reading that tells you a lot about a UFH system
In underfloor heating, Delta T is more than a number on a display.
It can help installers and specifiers understand whether a system is moving water correctly, transferring heat properly, and performing as the design intended.
Too high? You may be looking at restricted flow, trapped air, incorrect balancing or a loop that is not moving enough water.
Too low? It could be excessive flow, low demand, an open bypass, or simply a heat-pump-led system designed to run with a smaller temperature difference.
The important bit: don’t chase Delta T in isolation.
✅ Check the design.
✅ Check the heat source.
✅ Check whether the system is at steady state.
Then use the reading to confirm what the system is telling you.
We’ve put together a practical guide covering Delta T targets, common issues, commissioning checks and system balancing.
Read the full guide here: https://eu1.hubs.ly/H0vwNct0