Central Heating Leak Detection in Brackley

Symptoms

At a property in NN13, the combination boiler had been isolated from the heating circuit by others so the customer could continue using hot water. With the boiler supplying both heating and hot water, the heating circuit had been effectively shut down, and it became clear there was a leak somewhere within that circuit that needed to be traced before the system could be restored to full operation.

The heating circuit could not hold any pressure at all — when a pressure test was attempted, it was impossible to build pressure in the system, indicating a significant loss point somewhere in the pipework. The challenge was locating that point without unnecessary disruption to the property, which included oak flooring in the hallway area.

Central heating leak detection was required to find the source precisely, given that the pipework ran beneath finished flooring and no visible signs of the leak were accessible from above.

Methods Used

The investigation combined pressure testing, tracer gas, acoustic detection, and endoscope inspection to narrow the leak down from a wide area to a single precise point. Tracer gas was introduced to the heating circuit and produced high readings across several areas of the hallway, establishing that the leak zone was concentrated in that part of the property.

Acoustic investigation then identified loud noise signals at multiple locations in the hallway, with the strongest signal pinpointed to a cupboard within that space.

With the acoustic evidence pointing to the cupboard, a small hole was drilled through the flooring at that location. An endoscope was then inserted to view the pipework beneath without lifting the full floor.

This confirmed the leak source and its cause, allowing a targeted repair to be agreed with the customer. This methodical approach — standard practice in central heating leak detection — meant only the directly affected section of oak flooring needed to be lifted rather than carrying out wider and more disruptive access.

Investigation Process

1. 1
   Pressure Test Attempted

   A pressure test was carried out on the heating circuit. No pressure could be established in the system, confirming an active leak was present.

2. 2
   Tracer Gas Investigation

   Tracer gas was introduced to the heating circuit. High readings were detected across several locations in the hallway, focusing the investigation on that area.

3. 3
   Acoustic Investigation

   Acoustic equipment was used throughout the hallway and identified loud signals at multiple points. The strongest reading was pinpointed to a cupboard in the hallway.

4. 4
   Endoscope Investigation

   A small hole was drilled through the flooring in the cupboard. An endoscope was inserted and visually confirmed a leaking 15mm push fit elbow beneath the floor, with rodent damage identified as the cause.

5. 5
   Oak Flooring Lifted

   Following discussion with the customer, the oak flooring above the leak location was lifted to provide access to the damaged elbow.

6. 6
   Elbow Replaced

   The damaged 15mm push fit elbow was removed and replaced with a new fitting.

7. 7
   Pressure Test Passed

   The heating circuit was pressure tested at 2 bar for 15 minutes, which passed at the time of testing.

8. 8
   System Refilled and Heat Test

   The heating system was refilled with 14 radiators vented throughout the process. A heat test confirmed all 14 radiators were heating up correctly on completion.

9. 9
   Flooring Replaced

   The oak flooring was replaced following the repair. The customer was advised to contact a flooring contractor to refit the oak flooring to a finished standard.

Result & Outcome

The leak was located beneath the floor of a cupboard in the hallway at the property in NN13. The cause was a 15mm push fit elbow that had been nibbled by rodents, compromising the joint and allowing water to escape into the subfloor space. The endoscope confirmed the exact fitting and its condition before any flooring was lifted, meaning access was kept to the minimum necessary area.

The damaged elbow was replaced, and the heating circuit subsequently held 2 bar pressure for 15 minutes without loss. All 14 radiators were vented during the refill, and a heat test confirmed the full heating circuit was operating correctly once the boiler was reinstated.

For this central heating leak detection job, the combination of tracer gas, acoustic detection, and endoscope inspection avoided unnecessary disruption across the hallway and allowed a precise, targeted repair. The customer has been advised to engage a flooring contractor to finish the oak flooring reinstatement.