Siemens LME11 / LME21 / LME22 fault 10: Wiring error or internal error, output contacts, other faults
Ten red blinks mean the burner control found a wiring error, an internal error, a problem with its output contacts or another fault not covered by the other codes. Unlike the other codes, the alarm output at terminal 10 is OFF for this code.
Diagnose this with AI
Try Free Boiler Diagnostic Upload a keypad photo, the fault history or a parameter export from your Siemens LME11 / LME21 / LME22. InduQT compares the evidence and suggests the next useful checks.
When it happens
- Any point in the sequence, often at the first start after wiring work or after replacing the unit
Where it sits in the burner
Supervised function: Controller self-checks.
| Component | Signals to look at | How it fails |
|---|---|---|
| Burner management controller | Burner sequence state, Controller supply voltage | Controller internal fault; Configuration or commissioning data changed; Supply voltage, frequency or grounding problem; Electrical noise on signal wiring |
| Operating and safety limits | Running interlock / limit string, Steam pressure, Boiler water temperature, Drum / water level | Operating or safety limit open; Pressure or position switch out of adjustment; Welded, jumpered or miswired contact |
Likely causes and checks
1Wiring error at the plug-in base or burner
- Points to it
- Appears after the burner control, base or a burner component was replaced or rewired.
- Check
- With the plant isolated (all-polar), compare the base wiring with the connection diagram for the installed LME type and the burner wiring diagram.
2Fault on an output circuit
- Points to it
- A fan motor, ignition transformer or fuel valve recently failed or was replaced.
- Check
- Have the loads on the fan, ignition and fuel valve outputs checked against the data sheet ratings by a qualified electrician.
3Internal fault of the burner control
- Points to it
- Wiring proven correct and the code returns on every start; unit dropped, wet or very old.
- Check
- Siemens says not to open or modify the unit, and a unit that has been dropped must not be used. Replace it with the same type number.
Telling it apart
- 10 blinks is the only code with the alarm output at terminal 10 OFF.
- Low mains voltage is shown as yellow-red on the signal lamp, not as a blink code.
Evidence to collect
- Blink count after pressing reset for more than 3 seconds
- LME type and plug-in base type
- Any wiring or component changes before the fault
- Mains voltage at the burner control
Work on fuel trains, burners, pressure vessels and electrical equipment must be done by qualified personnel following the manufacturer’s documentation and local codes. Never bypass a safety device or interlock.