Siemens Electromechanical burner automatic controller LAL2.65

This electromechanical burner automatic controller (Siemens LAL2.65) is used for start-up and control of forced-draught oil burners of medium and high capacity. It is suited to multi-stage or modulating burners in intermittent operation, with electromechanical valve control. Air pressure is monitored via a functional check of the air pressure relay during start-up and operation. Yellow flame is monitored by a photoresistive sensor QRB1..., blue flame by a sensor RAR... with selenium photocell. Its operating values include supply voltage 230 V, safety time 5 s, pre-purge time 66.5 s, pre-ignition time 2.5 s, post-purge time 15 s, and start-up sequence duration 91 s.

When replacing a control box of this class, the exact series and type designation of the original unit must be known. Supply voltage, safety time, and pre-purge time are critical parameters that must match. The flame detection method (ionisation, UV, or IR) and the base or plug pattern also determine compatibility. Controls of this type are normally not interchangeable between series, even within the same brand. A replacement with a different safety time is a safety hazard, not merely a compatibility issue.