Siemens Actuator SQN13.170B9

The Siemens Actuator SQN13.170B9 is a compact electric drive designed for precise positioning of air dampers in small and medium power burners. It operates at a supply voltage of 24 V and delivers a nominal torque of 1 Nm, with a holding torque of 0.7 Nm. The actuator rotates counterclockwise over a 90° angle, with an adjustable runtime ranging from 5 to 120 seconds. It is intended for use in combustion control systems to regulate air supply for optimal fuel-air mixing.

When selecting a replacement actuator of this type, ensure the supply voltage, torque, runtime, rotation angle, and rotation direction match the original specifications. The actuator must be compatible with the burner control system and the mechanical mounting on the damper shaft. Verify the shaft coupling pattern and the presence of auxiliary switches for end-position feedback. Before installation, check that the damper moves freely to prevent immediate damage.

Common failures include stripped gear trains due to over-torque, failed end switches preventing correct positioning, or seized valve stems after inactivity. Symptoms may include the damper not reaching its intended position, erratic operation, or the burner failing to modulate correctly. Check for free movement of the damper and inspect the actuator for mechanical damage or electrical faults.