S.4 — Heating Mode Burner On Error (EcoTEC 65kW)

What does S.4 mean?

This indicates an error related to the EcoTEC 65kW boiler's burner being active in heating mode, possibly signaling an unexpected state or issue during its operation.

• Burner malfunction
• Control system error

Click steps to track your progress.

1. 1

   Turn off the boiler at the main power supply and restart it after a brief wait (e.g., 30 seconds).

2. 2

   Check your heating controls (thermostat, timer) to ensure they are set correctly.

3. 3

   If the error reoccurs, contact a qualified heating engineer for a full diagnosis of the burner and control system.