E16 displayed; controller indicates power supply or internal electronics error
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
Danger: Work on live mains circuits only if you are qualified. Otherwise, limit checks to visual inspection and call a technician.
- Verify that the mains voltage to the Defro furnace is within the specified range using a multimeter.
- Inspect the control box for signs of moisture, corrosion, or burnt components.
- Tighten all mains and earth connections at the terminal block.
- Ensure the furnace is not sharing a circuit with heavy loads that cause voltage dips.
Internal PCB repairs should not be attempted by end users. Replace the control board through an authorized Defro service partner if confirmed faulty.
Repair Difficulty
Required Part
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