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F.65

F.65 - Electronics overheating

Vaillant · ecoTEC plus Boilers

What does F.65 mean?

The boiler's internal electronics are overheating, possibly due to external factors or an internal component failure.

Common Causes

  • Electronics overheating due to external influences (e.g., poor ventilation, nearby heat source).
  • The boiler's internal electronics are defective.

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Press the reset button on the boiler display up to three times to try and clear the fault.

  2. 2

    Ensure that the boiler's ventilation openings are clear and not obstructed, allowing for proper airflow.

  3. 3

    Check for any external heat sources (e.g., other appliances) near the boiler that might be causing the electronics to overheat.

  4. 4

    If the fault persists, contact customer service, as the internal electronics might be defective.

Browse all codes in this manual (146)
Verified technical data. Last updated: April 2026

Related Faults

Communication fault (display/PCB)Communication fault - No communication with the PCBD.092 = 1D.092 = 1 — actoSTOR module connection errorF.0F.0 — Flow–NTC open circuit
Source: Vaillant ecoTEC plus Boilers
Open Manual (Page 47)Search more codes in this manual