F.12 - actoSTOR cylinder charging sensor short circuit (with F.91)

What does F.12 mean?

There is a short circuit at the actoSTOR cylinder charging sensor (NTC). This fault occurs in combination with F.91, indicating a problem with the actoSTOR module.

• NTC sensor is defective.
• Short circuit in the cable harness.
• Cable is shorting to the casing.

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

   This fault is related to the actoSTOR module (F.91). Ensure the actoSTOR communication is working correctly by checking for other related faults.

3. 3

   Contact customer service. This indicates a short circuit in the actoSTOR cylinder charging sensor or its wiring, requiring professional diagnosis.