HVAC Procedure and Performance Guide

Replace fan wheel (cage fan)

Training for this procedure can be found in these courses:

                         131 – Oil Heat l  and  161 – Boilers l


Fan wheel must be replaced according to manufacturer’s specifications.  Fan wheel must be securely and correctly positioned on shaft, bearings must be correctly aligned and it must operate without vibration according to manufacturer’s specifications.  Fan wheel must be sized to specifications and must be rated for speed at which it will be driven.  Applicable safety procedures must be followed. 


        1. Review job order and manufacturer’s specifications.
        2. Determine diameter, width, number o vanes, bore size and speed rating for fan wheel.
        3. Collect tools, equipment and materials.
        4. Put on safety and protective equipment and apparel.
        5. Disconnect electrical power to equipment.
        6. Remove all safety guard(s).
        7. Remove drive belt and driven sheave from fan shaft.
        8. Remove shaft and wheel assembly from fan housing.
        9. Remove one end bearing and remove existing wheel.
        10. Verify that new wheel is suitable replacement.
        11. Install new wheel and secure it to shaft at correct location; reinstall bearing.
        12. Inspect shaft and bearings prior to reassembly and replace if defective.
        13. Install shaft and wheel assembly in fan housing and align bearings.
        14. Reinstall driven sheave, align sheaves and install and tension drive belt.
        15. Reconnect electrical power.
        16. Test fan operation:
        17. If excessive vibration, check for bent shaft or imbalance.
        18. If noisy, check for contact with fan housing.
        19. Make adjustments or replace defective components based upon findings in Step 15.
        20. Stop fan and replace safety guard(s).
        21. Leave equipment in required operating status.
        22. Remove safety and protective equipment and apparel.
        23. Gather tools, equipment and leftover materials, and leave work site clean.