Internal Cold Mains Leak Detection in Neston

Symptoms

With stop cock locations unconfirmed and no clear external indicators, this was not a straightforward internal leak detection job from the outset. The noise from the cylinder pointed toward the hot feed pipework, but the source and extent of any leak remained entirely unclear until a full investigation could be carried out.

Methods Used

An endoscope camera was introduced through a gap behind the bathroom tiles to inspect the pipework routing and check for isolation valves before any floor work began. The full investigation combined pressure testing, acoustic correlation and camera inspection to work through the problem systematically.

Investigation Process

1. 1
   Stop cock locations traced

   On arrival the internal and external stop cock locations were both unknown. Time was spent tracing and identifying both before any further work could proceed.

2. 2
   Water softener used for isolation

   The internal stop cock could not be readily accessed, so the water softener was isolated instead. This caused the cylinder noise to stop, providing a working isolation point.

3. 3
   Endoscope camera deployed behind bathroom tiles

   A camera was introduced through a gap behind the bathroom tiles to inspect the blue poly pipework and confirm whether any isolation valves were present — none were found.

4. 4
   Pipework traced to loft

   The pipework was followed from the bathroom area across to the loft in an attempt to locate the internal stop cock, but it was not found there.

5. 5
   Pressure test on hot feed pipework — first failure

   A pressure test was applied to the hot feed pipework. The test failed, confirming a leak was present somewhere on the system.

6. 6
   Acoustic anomaly detected in corridor

   The acoustic microphone was used to scan the floors and detected an anomaly beneath the corridor floor tiles.

7. 7
   Corridor floor opened — first leak found

   The corridor tiles and screed were exposed, revealing a plywood box containing pipework that was very wet. A leaking 15mm copper pipe was found and replaced with new copper pipe and fittings.

8. 8
   Pressure test repeated — second failure

   Following the first repair, the pipework was retested. It failed again, indicating a second leak remained on the system.

9. 9
   Acoustic anomaly detected in bathroom

   Further acoustic scanning identified a second anomaly beneath the bathroom floor tiles.

10. 10
    Bathroom floor opened — second leak found

    The bathroom tiles and screed were exposed, revealing a second wet plywood box. A leaking 22mm copper tee soldered fitting was found and replaced with new copper pipe and fittings.

11. 11
    Final pressure test passed

    The pipework was tested at 3 bar for 20 minutes. The test passed, confirming no further leaks were present on the system at the time of testing.

Result & Outcome

The exposed floor areas should be left open to allow the screed and subfloor to dry out fully before any reinstatement. The customer has also been advised to confirm with the water board the location of the external main stop cock, and to have the internal main stop cock properly addressed once identified.