Dual Fuel Burner Operation Procedure: Oil, Gas and Mixed Combustion Guide

switch modes Meta Description: Explore the complete dual fuel burner operation procedure for gas-only, oil-only, and mixed combustion. Follow step-by-step manual & automatic operations, servo motor settings, and fault code troubleshooting for safe, efficient burner running.

A dual fuel burner is a core thermal processing equipment widely applied in industrial heating systems. It supports three flexible combustion modes: pure oil combustion, pure gas combustion, and oil-gas mixed combustion. Strictly following standardized operation procedures is essential to guarantee stable burner operation, eliminate potential safety risks, reduce equipment failure rates, and prolong the service life of industrial burners.

This comprehensive guide details the full dual fuel burner operation procedure, covering pre-operation safety checks, step-by-step manual and automatic operation for all combustion modes, precise servo motor air damper adjustment methods, and professional fault code diagnosis and repair solutions. It serves as a standardized operation and maintenance manual for on-site industrial operators and technical maintenance personnel.

Pre-Operation Preparations & Warnings

To ensure personnel safety, stable ignition and normal operation of the oil-gas dual-purpose burner, complete the following standard pre-operation inspections and adjustments before any startup operation:

• Priority Pilot Burner Debugging: Always test and debug the ignition torch in advance before formal gas combustion operation to ensure reliable ignition performance and avoid ignition failure.
• Strict Gas Pressure Regulation: Maintain the front-end gas valve pressure steadily between 0.01Mpa and 0.04Mpa. Never initiate ignition if the gas pressure is unstable, excessive or insufficient.
• Standard Pre-Ignition Setup: After confirming qualified gas pressure, fully close the small manual ignition valve first. Switch the control box function key to manual mode (manual indicator lights up), then activate the fan key to open the air damper for pre-purging.
• Optimize Pilot Flame Status: Press the ignition key to close the air damper (ignition indicator lights up). Slowly open the small manual ignition valve and fine-tune the gas volume to achieve the optimal stable pilot flame. After calibration, press the stop key to place the system in standby mode.

1. Single Oil Combustion Operation Procedure

Turn the burner conversion switch to the oil combustion position, and the PLC display will synchronously show the oil-only combustion mode. The system is equipped with two operating modes: manual and automatic. The detailed standard operation steps are outlined below:

1.1 Manual Oil Combustion Operation Steps

1. System Reset: Press the Stop key to reset the entire system and clear abnormal status records.
2. Manual Standby Activation: Press the Function key to turn on the manual indicator, and the system enters manual standby mode.
3. Stable Oil Pressure Adjustment: Open the oil return valve and press the Oil Pump key to start the oil pump. Adjust the oil return volume to reach the standard working oil pressure. Press the key again to shut down the oil pump when pressure stabilization is achieved.
4. Electric Heater Activation: Open the oil inlet valve until the electric heater is completely filled with fuel oil. Press the Heating key to activate the electric heating rods installed on the oil inlet seat and nozzle seat for fuel preheating.
5. Temperature Calibration & Cold Oil Drainage: Set the electric heater’s working temperature to 140°C. When the heating indicator turns off (indicating the preset temperature is reached), open the burner’s built-in oil return valve to drain all cold oil inside the hose in front of the solenoid valve. Then slightly tighten or fully close the oil return valve.
6. Full Furnace Purge: Press the Fan key to start the fan, and the controller will display the air distribution status. The air damper will automatically open according to the 0-9 gear preset by the servo motor. Note for manual air damper models: Fully close the damper before starting the fan; slowly open the damper after the fan runs stably to thoroughly purge the furnace chamber.
7. Controlled Ignition Operation: Press the Ignition key to close the air damper and activate the igniter. After a 5-second delay, the ignition gas valve opens to complete pilot ignition. Observe the flame condition through the burner’s fire viewing window. If ignition fails, turn off the ignition system, open the air damper to purge residual gas, troubleshoot the fault, and repeat the ignition procedure.
8. Main Fuel Combustion Activation: After successful stable pilot ignition, press the Main Valve key to open the fuel solenoid valve. The air damper automatically adjusts to the preset gear position. Once stable main flame combustion is confirmed, the system will automatically start flame real-time monitoring. Note for manual air damper models: Slowly adjust the damper to the optimal opening position after the main valve is opened and ignited.
9. Enable Automatic Safety Protection: After verifying normal burner combustion operation, press theFunction key to switch the system to automatic mode, enabling the full-range automatic safety protection function.

1.2 Automatic Oil Combustion Operation Steps

10. Press the Stop key to fully reset the system and clear all abnormal working records.
11. Press the Confirm key to trigger automatic fan startup, and the system will perform a standard 60-second furnace purging process to eliminate residual gas.
12. Upon completion of furnace purging, the air damper will automatically close with a 10-second delay. The igniter and ignition gas valve work simultaneously to complete pilot ignition.
13. The main oil valve automatically opens after 5 seconds of stable pilot ignition. The air damper adjusts to the preset gear for stable main combustion, and the system enters real-time flame monitoring and automatic safety protection state.

2. Oil-Gas Mixed Combustion Operation Procedure

The oil-gas mixed combustion mode supports simultaneous supply of oil and gas fuels, adapting to industrial heating scenarios with variable load demands. This mode requires stricter control of oil pressure and preheating temperature to ensure efficient and safe mixed combustion.

2.1 Manual Mixed Combustion Operation

14. Toggle the conversion switch to the mixed combustion position, and the PLC display will show the mixed combustion operating mode.
15. Press the Stop key for system reset, then press the Function key to enter manual mode.
16. Adjust the fuel supply pressure to the standard 1.2Mpa, then open the inlet valve of the electric heater.
17. Set the electric heater temperature to 140°C and press the Heating key to start fuel preheating.
18. When the heating indicator turns off (temperature reaches the preset standard), open the oil return valve to drain cold oil until the fuel pipeline is fully heated, then properly close the oil return valve.
19. Start the fan to complete furnace purging, then activate the ignition system to calibrate and stabilize the pilot flame.
20. After stable pilot ignition, press the Main Gas Valve key to adjust the air damper to the 1st fire position, then press the Auxiliary Oil Valve key to switch the air damper to the 2nd fire position.
21. Close the manual gas valve after stable oil combustion is achieved, and press the function key to switch the system to automatic safety protection mode.

2.2 Automatic Mixed Combustion Operation

22. Switch to mixed combustion mode and press the Stop key to reset the system completely.
23. Press the Confirm key to automatically start the oil pump and electric heater. The fan will initiate a 60-second automatic furnace purge once the fuel temperature reaches 140°C.
24. After purging, the system performs delayed ignition, and the main gas valve opens 5 seconds later. Set the servo motor gear between 1 and 3 to adapt to gas combustion.
25. The auxiliary oil valve automatically opens after 15 seconds of stable gas combustion. Adjust the servo motor gear to 1-9 for full-power mixed combustion, and the system will enter automatic operation and monitoring mode.

3. Single Gas Combustion Operation Procedure

Single gas combustion is a clean, energy-efficient and low-failure operating mode for dual fuel burners, featuring simple operation and stable combustion performance:

26. Switch the burner mode to gas combustion, and the PLC will display the gas-only operating status.
27. Press the Function key to enter manual mode, then start the fan to open the air damper and complete furnace purging.
28. Press the Ignition key to activate the igniter, and open the main gas valve after successful pilot ignition.
29. Fine-tune the air damper to the optimal combustion opening (manual damper models require slow and gradual adjustment).
30. Switch to automatic mode after stable combustion to activate the system’s automatic safety protection function.
31. Automatic Quick Start Operation: For daily routine use, simply switch to gas mode, open the manual valve of the gas pipeline, and press the Confirm key to realize one-click automatic operation.

4. Servo Motor Air Damper Adjustment Guidelines

The burner is equipped with a servo motor featuring a 0-9 digital gear adjustment system. It precisely controls the air damper opening to adjust the air-fuel ratio, which directly determines combustion efficiency and operational stability:

• Red Indicator (0 Gear): Default shutdown state, corresponding to the fully closed air damper position (factory standard setting).
• Yellow Indicator (Middle Gear): Corresponding to the 1st fire opening position, adjustable flexibly according to actual equipment load requirements.
• Adjustment Precautions: Gear parameter modifications only take effect when the corresponding indicator is lit. The gear value can be adjusted in real time during burner operation to optimize the air-fuel ratio and combustion effect.

5. Burner Fault Code Diagnosis & Troubleshooting

The dual fuel burner controller is designed with digital fault code display function, enabling technicians to quickly locate faults and conduct targeted maintenance. The detailed explanation and troubleshooting methods for common fault codes are as follows:

• Code 0: Normal working or standby state, no system faults detected.
• Code 1: False flame signal detected before ignition. Causes: Short circuit or sensitivity deviation of the photosensitive tube or UV detection tube. Solution: Power off the equipment for inspection, and adjust the RTL adjustable resistor on the control board to calibrate flame detection sensitivity accurately.
• Code 2: Main valve ignition failure. Common causes: Excessive air distribution, poor fuel supply, nozzle blockage or dirty photosensitive tube. Solution: Clean the nozzle and photosensitive tube, adjust air volume and detection sensitivity, then perform re-ignition after troubleshooting.
• Code 3: Flame extinguishment after the ignition system stops working. Causes: Excessive fan air volume, unstable oil or gas supply pressure. Solution: Appropriately reduce the air damper opening, check and stabilize fuel pressure, then restart the equipment.
• Code 4: Fan motor overcurrent fault. Solution: Press the thermal overload reset switch, inspect the three-phase power supply, motor circuit and contactor conductivity to eliminate circuit faults.
• Code 5: Oil pump motor overcurrent fault. Solution: Reset the overload protector, inspect the oil pump circuit, electric heater operating status and contactor conductivity to fix circuit and equipment abnormalities.
• Code 6: Automatic shutdown of the auxiliary valve. Causes: Abnormal load parameters (low system pressure, temperature or water level) or incorrect 2nd fire gear setting. Solution: Switch the 2nd fire switch to gear 2 to restore full-power operation.
• Code 7: Both main and auxiliary valves are closed, system in standby state. Alternating flashing of Code 0 and 7 indicates deviated load parameters; the system will automatically resume operation once parameters return to normal ranges.

6. Daily Operation Safety Tips

1. For burners burning heavy oil or crude oil, ensure continuous and stable supply of ignition gas at all times to prevent ignition failure caused by gas shortage.

2. Perform a complete furnace purge before every formal ignition to eliminate residual fuel gas in the chamber and prevent explosion safety hazards.

3. Immediately stop operation and cut off the fuel supply once a fault code appears. Do not force start the burner to avoid secondary equipment damage or safety accidents.

4. Regularly clean the photosensitive tube, fuel nozzle and air duct to block dust and carbon deposition, ensuring long-term efficient and stable combustion of the burner.

FAQ About Dual Fuel Burner Operation

Q1: Why does the burner fail to ignite after turning on the main valve?

A: This fault is mainly caused by excessive air damper opening, blocked fuel nozzles, abnormal oil/gas pressure, or dirty and insensitive flame detection sensors. You need to adjust the air-fuel ratio, clean blocked accessories, calibrate fuel pressure, and then re-ignite the burner.

Q2: What is the standard working temperature of the burner electric heater?

A: The electric heater of the dual fuel burner adopts a fixed standard working temperature of 140°C. This temperature ensures full atomization of fuel oil, effectively avoids incomplete combustion, and reduces carbon deposition and equipment failure risks.

Q3: How to switch between manual and automatic modes correctly?

A: The standard operation is to complete ignition and maintain stable combustion in manual mode first, then press the function key to switch to automatic protection mode. Mode switching is prohibited during ignition startup or system fault status.during ignition or fault status.