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- First-floor flat: a leak on old pipework nobody knew was live
A first-floor flat, a meter that never stopped, and old hot pipework left live after a boiler conversion
The meter showed a small leak with no water in use. When the flat was converted to a combination boiler, some old hot pipework had been left buried under the bathroom floor, still connected and under pressure.
What was happening
The external water meter showed a small but active leak with no water in use. The two-bedroom first-floor flat had a combination boiler, fitted when the property was converted from an open-vented hot water cylinder system. Not all of the old pipework had been taken out during that work.
What the engineer did
The hot feed was cut into and pressurised to 2 bar, and a gradual drop on the gauge confirmed a leak. Acoustic listening on the hallway and bathroom floors picked up water escaping through buried pipework. Tracer gas put in at 2.4 bar travelled through the pipes and surfaced at the leak point, which was traced to an area below the flat. A look under the bath showed how the old hot pipework was still connected.
What was found
The leak was on redundant hot water pipework from the old installation, buried under the bathroom floor. It was still joined to the hot tap feed through an isolation valve, so it had stayed under pressure.
What happened next
ADI capped off the old buried pipework and reconnected the hot tap feed directly to the newer pipework, taking the redundant section out of the live system altogether.
If you manage rentals
Renovation history matters. If a property has had a boiler conversion or a new bathroom, tell the office when you call: old pipework left in place is a common hiding place, and following it may mean getting into the flat below.
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