EOGB Servo Motor SQN75.254A21B

The Servo Motor SQN75.254A21B is a burner servo motor supplied under the EOGB brand and listed for EOGB, Siemens and Landis boiler applications. It provides the motorised actuation used within the burner's control sequence, moving the air and fuel control linkage between its set positions. It is a serviceable component of the burner assembly rather than a boiler-wide part.

• The burner fails to reach or hold its correct firing position and goes to lockout during start-up.
• The damper or linkage does not move as the burner runs through pre-purge and ignition.
• The motor runs but the actuator output does not change position, or it hunts continuously.
• Signs of overheating, a burnt smell, or mechanical slack and backlash at the actuator coupling.
• The control board reports an actuator or position feedback fault.

• Confirm the part number on the existing motor matches SQN75.254A21B exactly, as suffix codes denote different shaft, cam and running-time variants.
• Check the appliance data plate to confirm the EOGB, Siemens or Landis fitment before ordering.
• Inspect the wiring loom, plug and actuator linkage for damage that could imitate a motor fault.
• Note the existing actuator position, cam settings and linkage adjustment before removal so the replacement can be set up to match.