OEM Controller LOA24.171B27

OEM Controller LOA44.281B27

Siemens LOA24.171B27

Siemens LOA44.281B27

Siemens LOA24.171B27 Burner Controller: A Robust Solution for Oil Burner Management

The Siemens LOA24.171B27 Burner Controller is a specialized control unit designed for the startup, supervision, and control of oil burners operating in intermittent mode. Engineered for 2‑stage forced draft oil burners with oil throughput up to 30 kg/h, this controller offers precise timing and safety features essential for reliable combustion management in industrial and commercial heating systems.

Overview

The LOA24.171B27 is part of Siemens’ range of burner controllers used in oil burner systems. It plays a critical role in ensuring that burners start reliably, operate safely, and shut down in case of fault conditions. This controller is engineered to manage both the ignition sequence and flame supervision by integrating key timing functions and safety mechanisms.

Key Features

• 2‑Stage Burner Control:
  Designed specifically for oil burners with a two‑stage firing process, the LOA24.171B27 ensures efficient combustion control under varying operating conditions.
• Precise Timing Parameters:
  The controller features a prepurge time (t₁) of 13 seconds, an ignition safety period (TSA) of 10 seconds, and a long postignition time (t₃ₙ) ranging from 15 to 20 seconds. These timings are critical to guarantee a stable ignition and continuous burner operation.
• Robust Flame Supervision:
  For flame detection, the system uses photoresistive detectors—QRB for yellow-burning flames and QRC for blue-burning flames. This dual approach helps in accurately monitoring the flame and quickly initiating lockout if a flame failure occurs.
• Undervoltage Detection and Safety Lockout:
  The unit continuously monitors the supply voltage to ensure it remains within acceptable limits. In the event of an undervoltage or unstable flame conditions, the controller will trigger a safety lockout to prevent hazardous operation.
• Durable Mechanical Design:
  Housed in impact‑proof, heat‑resistant, and flame‑retarding plastic, the LOA24.171B27 is built to endure the rigors of industrial environments. Its plug‑in design ensures a secure and audible engagement with its base, simplifying installation and maintenance.
• User-Friendly Diagnostics:
  An integrated lockout reset button with a built‑in fault indication lamp offers clear visual feedback on operational status and error conditions, making troubleshooting straightforward for maintenance personnel.

Technical Specifications

• Model: LOA24.171B27
• Application: Oil burner control for 1‑ or 2‑stage forced draft burners
• Timing Parameters:
  • t₁ (Prepurge Time): 13 seconds
  • TSA (Ignition Safety Time): 10 seconds
  • t₃ₙ (Long Postignition Time): 15–20 seconds
• Operating Voltage: AC 220–240V
• Operating Mode: Intermittent operation
• Detection: Uses photoresistive flame detectors (QRB and QRC) for supervising yellow and blue flames
• Degree of Protection: Typically IP40 (installation dependent)
• Construction: Compact, plug‑in design made from durable, flame‑retarding plastic

Note: The LOA24.171B27 can be replaced by LMO14.111C2 or LMO24.111C2 in certain applications, providing flexibility in system upgrades.

Applications

The Siemens LOA24.171B27 Burner Controller is widely used in various settings where reliable oil burner operation is critical. Common applications include:

• Industrial Heating Systems:
  In factories and large-scale processing plants, the controller ensures that oil burners operate safely and efficiently, contributing to overall process stability.
• Commercial Boilers and Furnaces:
  Used in commercial buildings and institutional facilities, the unit maintains reliable burner operation and prevents downtime due to flame detection faults.
• Residential and Small-Scale Installations:
  Although primarily engineered for industrial use, the controller’s robust performance and safety features also make it suitable for high-end residential applications requiring precise burner management.

Installation and Operation

Proper installation and commissioning are essential for optimal performance. Key steps include:

1. Wiring and Mounting:
   • Follow Siemens’ detailed installation manuals to ensure correct wiring and adherence to safety standards.
   • The plug‑in design simplifies mounting, ensuring an audible engagement with the base that confirms a secure connection.
2. Commissioning:
   • Perform all pre-installation safety checks, including isolation of the mains supply and verification of connection integrity.
   • Test the prepurge, ignition, and postignition timing functions to confirm that the controller operates within specified parameters.
3. Routine Diagnostics:
   • Use the integrated lockout reset button and fault indication lamp to monitor system status.
   • Regularly inspect the flame detection sensors and wiring to maintain optimal performance and safety.

Benefits and Competitive Edge

The LOA24.171B27 stands out for its:

• Enhanced Safety: Advanced flame supervision and undervoltage detection minimize the risk of burner failure and potential hazards.
• Precision Control: Accurate timing parameters ensure that burners start reliably and operate consistently.
• Robust Construction: Designed to withstand industrial conditions, it delivers long‑term reliability and reduced maintenance costs.
• Ease of Use: User-friendly diagnostics and a simple plug‑in installation process make system integration and troubleshooting straightforward.

Conclusion

The Siemens LOA24.171B27 Burner Controller is a dependable and efficient solution for managing oil burners in a range of industrial, commercial, and residential applications. With its precise timing, robust safety features, and durable design, it ensures reliable burner operation and enhances overall system efficiency. Backed by Siemens’ engineering excellence, this controller remains a trusted choice for professionals seeking optimal performance in oil burner management.