Recent fitting or pipework changes can make installation history important. The installer may hold route, model and commissioning information needed for assessment.
What the observation means
That does not prove the installation caused the fault. The current appliance and its connected fixtures still need an accurate description.
A useful next step
Keep work dates and records available, especially if symptoms began soon afterwards. Do not modify the route to test a suspected installation issue. Distinguish breakdown repair from correcting or redesigning the fitted system so the appropriate responsibility and scope can be discussed.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.