Plug In Fans

Project: AHU Fan Conversion 
Duration: 30 Days
Value: £150,000

A client requested to convert 8 Air Handling Units from belt driven units to direct driven with the aim of increasing the air flow, reducing maintenance labour costs and reducing the energy consumption from the applications.

Phase 1 was to prove the existing air flow, survey the units and specify a range of plug in fans that could be fitted within the AHU Panels.

Phase 2, was the purchase the required materials, which were stored on site. The existing drive units were then removed and disposed of, new frame work (pre-fabricated off site) was fixed to floor of the AHU and the new  fans were then installed. New panelling to coil face was installed and the dampers moved. AHU panels plugged where the old equipment had been removed to ensure there were no air leaks within the chamber. The system was then tested and new airflow readings taken, resulting in an increase in air flow.

The final phase was to complete the remaining 7 AHU’s.

Final Results
Plant Ref Before Conversion After Conversion
AHU 1 supply 11.457 m3/s 16.316 m3/s
AHU 1 extract 14.952 m3/s 15.073 m3/s
AHU 2 supply 11.334 m3/s 17.998 m3/s
AHU 2 extract 12.529 m3/s 14.138 m3/s
AHU 3 supply 12.830 m3/s 14.289 m3/s
AHU 3 extract 10.873 m3/s 14.439 m3/s
AHU 4 supply 11.410 m3/s 16.019 m3/s
AHU 4 extract 8.644 m3/s 14.314 m3/s


Maintenance Cost Before After
Monthly PPM (based on 3 hours) £1560.00 £65
Drive Belt Replacement £640.00 Nil
Motor & Fan Bearing Grease £11.80 per visit Nil
Replacement Drive (Pulleys) per year £1860.00 Nil