The common faults of gas steam boilers can be divided into the following five categories, which require targeted troubleshooting and treatment:
1、 Ignition system malfunction
1. Can't light it up
Reason: Abnormal gas pressure (too low/too high), carbon deposition or spacing deviation of ignition electrodes (standard 2-3mm), and fouling of flame detectors.
Processing: Calibrate the gas pressure to 0.7-1.2 kPa; Clean the electrodes and adjust the spacing; Replace damaged UV probes or ionization electrodes.
2. Turn off the engine within 5 seconds after ignition
Reason: Imbalance of air-fuel ratio (excessive/insufficient opening of the throttle), failure of the solenoid valve seal.
Solution: Adjust the air damper to maintain the excess air coefficient at 1.1-1.3; Test the sealing of the solenoid valve and replace it if necessary.
2、 Abnormal gas supply
1. Lack of gas or pressure
Reason: Malfunction of pressure regulating station, accidental triggering of emergency shut-off valve (such as false alarm of gas probe), filter blockage or pipeline leakage.
Solution: Check the output pressure of the regulator; Reset the emergency shut-off valve and investigate the cause of false alarms; Clean the gas filter cotton; Use a pressure gauge to detect pipeline leaks and repair them.
2. Excessive pressure fluctuations
Reason: Failure of pressure regulating valve and unstable gas supply flow.
Solution: Replace the pressure regulating valve; Check the operation status of the gas meter to ensure stable external gas supply.
3、 Abnormal combustion
1. Unstable flame or flameout
Reason: nozzle blockage/wear, burner carbon deposition, servo motor cam offset.
Solution: unclog or replace the nozzle; Clean up carbon deposits in the combustion chamber; Calibrate the cam angle of the servo motor.
2. Flame turns red/skewed
Reason: Insufficient air supply or damaged nozzle.
Solution: Increase the opening of the air door to improve oxygen supply; Replace the deformed nozzle and calibrate the direction of gas injection.
3. Abnormal smoke exhaust (white smoke/thick smoke)
Reason: Insufficient combustion caused by low exhaust temperature (humid and cold environment), excessive or insufficient air volume.
Solution: Reduce air intake (white smoke) or increase air distribution (thick smoke); Install a flue gas waste heat recovery device to increase temperature.
4、 Mechanical and control system malfunction
1. Burner motor stops running
Reason: Abnormal voltage, open circuit of thermal relay, or motor coil resistance exceeding the limit (>50 Ω).
Solution: Check the circuit fuse; Reset or replace the thermal relay; Test the motor coil and replace it if it exceeds the standard.
2. Leakage or abnormal tripping of safety valve
Reason: The take-off pressure deviates from the design value (standard is 1.05 times the working pressure), and the sealing surface is damaged.
Processing: Calibrate the safety valve popping pressure; Grind or replace the valve core.
3. Abnormal water pump/fan
Reason: Bearing wear (loud noise), impeller imbalance (vibration).
Solution: Replace the water pump bearings; Strengthen the fan base and optimize the airflow channel.
5、 Electrical and water level faults
1. Abnormal display on water level gauge
Reason: Sensor malfunction or water pressure exceeding the limit.
Processing: Clean the electrode probe; Adjust the inlet valve to restore the pressure to the normal range.
2. Controller error (such as code H251)
Solution: Press the reset button to clear temporary faults; Retrieve historical fault records (supporting storage of 10 records) and analyze the root cause.
Operation standard: Before troubleshooting, be sure to cut off the power and gas sources! Immediately ventilate in case of gas leakage and prohibit the use of electric spark devices. Regularly cleaning filters, verifying safety valve pressure, and recording controller fault codes can prevent over 80% of faults.