Underfloor heating that began losing pressure after new carpet
The property
A newer detached house with underfloor heating across the ground floor. Each heating loop has its own valve on the manifold, a valve block in the understairs cupboard.
The problem
Soon after new carpet went into the lounge, the owners found the boiler gauge low most evenings. Their boiler engineer had passed the boiler, and nothing looked damp.
How we found it
Closing each loop's valve in turn showed only the lounge loop losing pressure. Tracer gas fed into it was picked up beside the skirting, and the warmed floor showed the same spot on camera.
The outcome
Lifting the carpet edge at the mark showed a gripper nail through the pipe. That length was repaired, quoted separately, and the carpet went back down.