E05
Klimosz
Flow Temperature Sensor (NTC) Fault
Boiler shows E05, no heating, temperature reading is unrealistic (very low or very high).
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
Open-circuit or shorted flow NTC sensor, Damaged sensor wiring harness, Corroded connector on main control board, Water ingress into sensor pocket
How to Fix / Troubleshooting
Safety: Isolate power before accessing internal wiring.
- Check sensor connection: Locate the flow NTC sensor on the Klimosz heat exchanger flow pipe. Ensure the plug is firmly connected and free of corrosion.
- Inspect wiring: Follow the cable from the NTC to the control board. Look for cuts, crushed sections, or signs of overheating. Repair or replace damaged wiring.
- Measure resistance: With the boiler off and wires disconnected, measure the NTC resistance using a multimeter. Compare with Klimosz resistance/temperature chart (e.g., around 10 kΩ at 25°C). If reading is open or near 0 Ω, replace the sensor.
- Dry sensor pocket: If there is water or condensation around the sensor pocket, dry it and check for leaks in the heat exchanger or fittings.
- Reset and test: Reconnect everything, restore power, and reset the boiler. If E05 persists, the control board input may be faulty and require replacement.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
Flow NTC Temperature Sensor
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements