Central Heating Leak Detection in Chelmsford

Symptoms

The property in CO6 had a pressurised central heating system that was not performing correctly. The setup included a boiler in the utility room, a pressurised hot water tank in an upstairs bedroom, and 15 radiators throughout.

Concrete floors ran throughout, covered by a mix of tiles, wood, and carpet, making any subsurface pipework difficult to access without targeted investigation.

A central heating leak detection was needed to identify where the system was losing pressure or water. Prior to the visit, the heating had not been functioning well enough to use thermal imaging as a diagnostic tool, which meant the investigation would rely on other methods to trace the fault.

Visible signs of a problem were present before any testing began — skirting board behind the fridge freezer had started to pull away from the wall, consistent with sustained moisture exposure beneath or behind it.

Methods Used

With thermal imaging ruled out due to insufficient heating performance, the approach shifted to tracer gas combined with acoustic listening and damp metering. The heating system was fully drained via the two drain points — one at the front of the property, one at the rear — before tracer gas was introduced through the filling loop.

This allowed the engineer to walk the property methodically and detect where gas was escaping through the structure.

For a central heating leak detection job of this type — concrete floors, multiple radiators, and pipework in poor condition — tracer gas is well-suited because it can penetrate floor and wall materials to identify a leak zone without unnecessary exposure work. Once the gas readings pointed to a specific area and acoustic and damp meter readings confirmed moisture, the wall was opened to expose the pipework directly.

Investigation Process

1. 1
   System drained down

   The heating system was fully drained using both drain points — one at the back of the property and one at the front — in preparation for tracer gas introduction.

2. 2
   Tracer gas introduced

   Tracer gas was connected to the heating pipework via the filling loop and allowed to pressurrise through the system.

3. 3
   Positive gas reading behind fridge freezer

   After a short period, tracer gas readings were detected behind the fridge freezer. The skirting board in the same area was also visibly lifting away from the wall.

4. 4
   Acoustic and damp meter confirmation

   A leak noise was audible in the area, and the damp meter returned elevated readings on both the adjacent wall and floor, confirming the leak location.

5. 5
   Area exposed and leak found

   The wall was opened along the skirting to access the pipework, revealing a leaking push fit fitting in very poor condition.

6. 6
   Repair carried out

   The failed fitting was cut out and replaced using two push fit couplers and 15mm copper pipe work; a soldered repair was not possible given the deteriorated state of the existing pipework.

7. 7
   System cleared and refilled

   Tracer gas was pushed through the full system with no further leaks detected and pressure holding. The heating system was then refilled and checked to confirm everything was working before the engineer left site.

Result & Outcome

The leak was found behind the fridge freezer, coming from a push fit fitting on the heating pipework running along the wall. The fitting had deteriorated to the point where a soldered repair was not viable, so it was cut out entirely and replaced with two push fit couplers and 15mm copper pipe work.

Following the repair, tracer gas was run through the full system again with no further leaks identified and pressure holding. The system was refilled and confirmed to be in working order before the engineer left. For a central heating leak detection job with this many radiators and concrete floors throughout, achieving a clean gas pass after repair gives a reliable confirmation that no additional faults are present in the accessible pipework.

The engineer noted that the pipework across the property is in poor condition and recommended replacing as much of the copper pipe work as possible to reduce the risk of further leaks developing at other fittings.