Boiler leaks water from underneath or from internal components.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety: Isolate power and, if leak is significant, close the boiler's isolation valves and cold water inlet to prevent further damage.
Steps:
- Remove the front panel (if user‑serviceable) and visually inspect for the source of the leak using a torch.
- Check the PRV discharge pipe outside; if water is running, the PRV may be passing.
- Place a tray or towels under the boiler to protect surfaces.
Most internal leaks (pump, heat exchanger, PRV, air vent) require parts replacement by a heating engineer. Do not ignore leaks, as they can damage the PCB and other components.
Repair Difficulty
Required Part
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