Falling pressure, but every underfloor loop held
The property
A detached house on the newer eastern side, with water-filled underfloor heating downstairs, a manifold in the utility cupboard and tiles throughout.
The problem
Every few days the gauge sank below one bar and had to be refilled, but no damp showed anywhere. The owners blamed a split floor loop.
How we found it
Each loop held at the manifold, so the loss lay on the flow pipe from the boiler. Thermal imaging traced it under the dining room once warm, and a pressure test agreed.
The outcome
Two dining room tiles were marked and photographed over the leak. Cutting in and joining the pipe was quoted separately, and the loops were left alone.