d1 — No feedback voltage from LSM 5

What does d1 mean?

The boiler is not receiving the expected feedback voltage signal from the LSM 5 unit. This unit is typically involved in controlling the exhaust flap, affecting safe flue gas operation.

• The wiring connecting the LSM 5 unit is incorrect, damaged, or disconnected.
• The exhaust flap is stuck, obstructed, or not operating correctly.
• A malfunction of the LSM 5 unit itself.

Click steps to track your progress.

1. 1

   Check the wiring of the LSM 5 unit for any damage, loose connections, or incorrect installation.

2. 2

   Inspect the exhaust flap for any obstructions or mechanical issues that might prevent its movement.

3. 3

   Ensure all electrical connections to the LSM 5 unit are secure and properly seated.

4. 4

   If wiring and the flap appear functional, the LSM 5 unit may require professional inspection or replacement.