Central Heating Leak Detection in Portsmouth

Symptoms

The customer at a property in PO5 reported that, following recent building works, the boiler pressure had begun dropping within approximately one hour of being restored. As the property has a combination boiler, any sustained pressure loss causes the unit to shut down entirely, leaving the heating and hot water inoperable.

The timing of the pressure drops — directly linked to the recent building works — pointed strongly to a breach somewhere in the newly installed heating pipework. However, the exact location of any leak was unknown, and the pipework had been run concealed inside the walls, making visual inspection impossible without opening the structure.

Central heating leak detection was required to trace the hidden pipework, identify where the pressure loss was originating, and establish what access would be needed to carry out a repair.

Methods Used

The investigation began with thermal imaging to trace the heating pipework routes through the property. The pipe runs were successfully identified, but no thermal hotspots indicating an active leak were visible at the surface.

A moisture-meter survey was then conducted throughout the property, which revealed elevated readings in the back bedroom and the main bathroom — flagging areas of concern but not pinpointing the leak source.

With no definitive leak location established from non-invasive methods, the system was drained down, the remaining water compressed out, and tracer gas injected into the heating pipework. A gas analyser was used to take readings across the property, and a high concentration of tracer gas was detected at the rear of the lounge when the probe was placed into an existing access hole.

This directed the physical access investigation to that specific area. The builder who had carried out the recent works confirmed the pipework routes and provided photographs of the installation, agreeing to reinstate any walls opened during the central heating leak detection process.

Investigation Process

1. 1
   Thermal Imaging Survey

   Thermal imaging cameras were used to trace the heating pipework through the walls. The pipe routes were identified, but no hotspots suggesting an active leak were visible at the surface.

2. 2
   Moisture-Meter Survey

   A moisture-meter survey was carried out throughout the property. Elevated readings were found in the back bedroom and the main bathroom, indicating areas of dampness but not confirming the precise leak location.

3. 3
   System Drained and Compressed

   The heating system was fully drained down and the remaining water compressed out of the pipework in preparation for tracer gas injection.

4. 4
   Tracer Gas Injection and Analysis

   Tracer gas was injected into the heating pipework and a gas analyser was used to take readings throughout the property. High tracer-gas concentrations were detected at the rear of the lounge when the probe was placed into an existing access hole.

5. 5
   Builder Confirmation and Access Agreement

   The builder who had recently carried out work at the property confirmed the pipework installation and provided photographs. He agreed to reinstate any walls that needed to be opened to access the leak.

6. 6
   Access Made and Leak Located

   Access was made at the rear of the lounge. The leak was found to have been caused by pipework coated in a paint or tar-like substance, which prevented the pipe from sealing correctly inside the fitting.

7. 7
   Repair Carried Out

   The affected section of pipe and the faulty fitting were removed and replaced with new pipe, fitting, and inserts.

8. 8
   System Refilled and Checked

   The system was re-pressurised and refilled with central-heating inhibitor. No further leaks were detected.

Result & Outcome

The leak was located at the rear of the lounge, identified through tracer gas detection via an existing access hole. Once access was made to the wall, the cause became clear: the pipework installed during the recent building works had been coated in a paint or tar-like substance, which prevented the pipe from seating and sealing correctly inside the push-fit or compression fitting. This is an installation defect — not material failure or general wear.

The defective section of pipe and fitting were replaced, the system was re-pressurised, and central-heating inhibitor was added before the system was returned to service. No further pressure loss was detected after the repair.

For a central heating leak detection case like this, establishing liability is as important as finding the fault. The cause is directly attributable to the recent building works, and the customer has been advised to pass the invoice to the builder responsible for the defective installation. The builder has already agreed to reinstate any wall access made during the investigation.