Fault F3 - Low-loss header sensor or accessory issue

What does F3 mean?

This fault suggests a problem with the connections or wiring to the low-loss header sensor of the Cascade Control, or an issue with other accessories like the outdoor temperature sensor.

• Issues with connections/wiring to the low-loss header sensor of the Cascade Control
• Problems with other boiler accessories (e.g., outdoor temp. sensor)
• Defective Cascade Control unit

Click steps to track your progress.

1. 1

   Check all connections and wiring to the low-loss header sensor of the Cascade Control for looseness or damage.

2. 2

   Check other accessories, such as the outdoor temperature sensor, for proper connection and function.

3. 3

   If the problem persists, the Cascade Control unit may need to be checked or replaced by a professional.