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Vaillant F11 Fault Code
This page contains the information required to help repair and diagnose the fault codes being shown on the boiler display. The following information, will take you through the fault finding sequence or steps, for rectifying a Vaillant Ecotec boiler with this fault code. Suggested solutions will be detailed further down the page.
This fault according to Vaillant Instructions and Servicing manual is a Heating Flow NTC Thermistor Fault or Heating Return NTC short circuit
Cause of F11
- There Is A Short Circuit On The Heating Return NTC Thermistor (Should Read 12Kohms @ 20C)
- Wiring Harness Fault Or Connection Error Between The Heating Return NTC Thermistor And The Main PCB.
Solutions to repair this fault
Check the NTC sensor. Check the wiring using a continuity tester and resistance tester if necessary. Replace NTC, harness or PCB as necessary dependent on checks.
Models applicable to:
Ecotec Pro, Ecotec Plus, Ecotec Exclusive.
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