Water dripping from the tundish on a Gledhill unvented cylinder
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: The tundish discharge may be hot. Do not touch the water directly. Persistent discharge indicates a fault that must be corrected to maintain safety.
Steps:
- Check frequency: Occasional drips during heating can be normal. Continuous flow or frequent dripping is not.
- Test PRV: Briefly lift the test lever on the pressure relief valve to flush debris. If it continues to drip afterwards, the valve may need replacing.
- Expansion vessel: As described earlier, check and recharge the expansion vessel air side when the system is cold and depressurised.
- Inlet pressure: Have an engineer measure the mains pressure and verify the operation of the pressure reducing valve. Replace faulty valves as needed.
Note: Work on unvented safety devices must be carried out by a suitably qualified engineer in many jurisdictions.
Repair Difficulty
Required Part
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