Boiler frequently locks out and requires manual reset, but no specific error code is stored or displayed.
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 first: Repeated lockouts indicate an underlying fault that must be investigated; do not ignore.
User-level checks:
- Note the conditions when lockout occurs (DHW vs CH, weather, time of day) to help diagnosis.
- Ensure adequate ventilation around the boiler and that flue terminal is unobstructed.
Technical checks (qualified personnel):
- Inspect and tighten all electrical connections, especially earth and neutral.
- Check flame sensor, fan, and pump for intermittent operation.
- Monitor boiler operation with a multimeter or diagnostic tool to capture faults.
- Resolder or replace the PCB if dry joints or intermittent faults are suspected.
After corrective work, run extended tests in both CH and DHW modes to confirm reliability.
Repair Difficulty
Required Part
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