C3
Nibe
Internal sensor communication fault
C3 alarm, internal sensor bus error, multiple sensor readings missing
Advertisements
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.
Advertisements
Possible Causes
Shorted sensor bus wiring, failed sensor interface on PCB, moisture on connectors, incorrect sensor wiring
How to Fix / Troubleshooting
Safety: Isolate power before inspecting internal wiring.
- Visual inspection: Open the control compartment and look for signs of water ingress, corrosion, or burnt components on the sensor connectors.
- Disconnect suspect sensors: If one sensor or cable appears damaged, disconnect it and see if the alarm changes after power‑up (for technicians only).
- Dry and clean: Carefully dry any moisture and clean light corrosion with appropriate contact cleaner.
Persistent C3 alarms usually require control board diagnostics and possible replacement by a Nibe technician.
Advertisements
Repair Difficulty
Professional Required
5/5
Required Part
Sensor Interface PCB
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements