Air Handlers are manufacturers of Heating, Ventilating and Air Conditioning Equipment for the building services industry

Air Handlers Celebrating 25+ Years of Success 1989 - 2015

Operating and Maintenance Manual

Fan Section


Pre-Start Checks
After assembly of Air Handling unit the following checks should be made. Refer to Data Chart on General Arrangement drawing for specific details.

Isolate electric supply to fan-motor before entering the fan section.

Check pulleys/bushes are secure on shafts and that key is fitted.
Check belt tension, see drivebelt section of this manual for directions. Check that anti-vibration mountings are level and that bolts are tight Check motor terminal cover is secure and that bolts are tight.

Test Run
Test run the motor and drive to ensure that the fan is rotating in the right direction. The correct rotation direction is marked on the fan scroll. If the rotation is in reverse, stop the motor and reverse any two (2) incoming supply lines to the motor or starter (3 phase supply).

Check that the current being drawn by the motor does not exceed the motor full load current (indicated on the motor name plate). Note! All access panels must be closed during this test, otherwise false readings will be obtained.

After 30 minutes operation drive belts should be checked for tension and re-tensioned if required.

At least every 12 months a major inspection of the fan section should be carried out as follows:

Isolate electric supply to fan-motor.

Remove and examine drivebelts, check for uneven wear in belts which could indicate misalignment of pulleys or possible wear to fan bearing. Rotate and rock shafts of fan and motor to detect bearing play. Clean fan impeller, any build-up of grease and dust will affect the balance of the fan causing stresses and decreasing the bearing life. Inspect all internal and external surfaces for signs of deterioration. After Inspection and replacement carry out pre-start check and test run.