What is the reason for the decrease in EFU air volume? Troubleshooting sequence of filters, air intake and speed
Direct answer: The decrease in EFU air volume may be caused by an increase in filter resistance, obstruction of air inlet, change of control gear, dust accumulation in the fan, or changes in equipment structure. Effective troubleshooting requires retaining baseline data and eliminating items one by one in the order of 'Measurement - Control - Air Path - Components'.
Step 1: Confirm that the measurement results are comparable
Compare to original recording using the same instrument, grid of measurement points, measurement distances and equipment status. The decrease in a single measuring point does not necessarily represent a decrease in total air volume, but may also be a result of local obstruction or changes in airflow distribution.
Step Two: Verify Controls and Power
Check the working or duty mode, speed setting, communication instructions, power supply voltage and fault records. Batch equipment also needs to compare with other EFUs in the same area to determine whether it is a single machine problem or a change in system instructions.
Step 3: Check the air inlet path
Check whether there are new structures around the air inlet grille, upper cover, wiring harness, air return vent, and equipment. Dust or foreign objects should be cleaned according to maintenance requirements.
Step 4: Measure the filter pressure difference
Compare current differential pressure to new filter baseline and maintenance limits. Moisture, dust accumulation, or incorrect installation of the filter may increase resistance. It should be replaced when the replacement conditions are reached, rather than continuing to increase the speed.
Step 5: Check the fan and equipment resistance
Confirm impeller dust accumulation, abnormal wear, speed feedback, vibration and motor temperature rise. If an orifice plate or mechanism is added to the air outlet side of the equipment, the operating point of the system may also be changed.
Restoring baseline records after processing
After maintenance, re-record the air volume, wind speed, pressure difference, rotation speed, power and noise, and indicate the replacement parts and date to facilitate subsequent trend judgment.
FAQ
How much does the air flow drop require maintenance?
It should be judged based on the minimum air volume, key point wind speed or pressure difference limit set by the project, and it is not suitable to use a uniform ratio.
What should I do if the air volume is still low after replacing the filter?
Continue to check the air intake, control settings, fan status, seals and equipment additional resistance.
Can speed compensation be increased in the long term?
It is not recommended for long-term treatment. Power, noise, temperature rise and root cause of failure need to be evaluated.
How Aili Industrial helps troubleshoot the decrease in EFU air volume
When the EFU air volume decreases, it is recommended to first check whether the air filter resistance has increased, then check whether the air inlet is blocked or blocked, and then check the fan speed, control parameters, power status, and internal air ducts of the equipment. Checking in a fixed order can reduce repeated disassembly and assembly and invalid adjustments.
The filter will gradually accumulate dust during use. After the resistance increases, the actual working point of the EFU may change. If the filter status is normal, you need to check whether the air inlet space, protective net, air duct structure and control signal have changed. Dust accumulation on the fan impeller, abnormal motor operation, or loose fasteners may also affect the actual air volume.
Aili Industrial can assist in analysis by combining EFU model, initial test data, filter parameters and on-site operating conditions. It is recommended for batch equipment to record the initial air volume, speed, current and filter status to provide a basis for comparison for subsequent maintenance and fault judgment.
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Conclusion: If the EFU air volume decreases, you should first confirm the measurement method and control gear, and then check the air inlet, filter pressure difference, fan speed and equipment structure. Directly increasing the RPM may mask blockages or component anomalies.
