Fan Troubleshooting Guide

Low Capacity or Pressure

  • Incorrect direction of rotation. Make sure the fan rotates in same direction as the arrows on the motor or belt drive assembly.
  • Poor fan inlet conditions. There should be a straight clear duct at the inlet.
  • Improper wheel alignment.

Excessive Vibration and Noise

  • Damaged or unbalanced wheel.
  • Belts too loose; worn or oily belts.
  • Speed too high.
  • Incorrect direction of rotation. Make sure the fan rotates in same direction as the arrows on the motor or belt drive assembly.
  • Bearings need lubrication or replacement.
  • Fan surge

Overheated Motor

  • Motor improperly wired.
  • Incorrect direction of rotation. Make sure the fan rotates in same direction as the arrows on the motor or belt drive assembly.
  • Cooling air diverted or blocked.
  • Improper inlet clearance.
  • Incorrect fan RPM.
  • Incorrect voltage.

Overheated Bearings

  • Improper bearing lubrication.
  • Excessive belt tension.

Heat Gain form Occupants of Conditioned Spaces

Typical Application Sensible Heat
(BTU/HR)

Latent Heat
(BTU/HR)

Theater-Matinee 200 130
Theater-Evening 215 135
Offices, Hotels, Apartments 215 185
Retail & Department Stores 220 230
Drug Store 220 280
Bank 220 280
Restaurant 240 310
Factory 240 510
Dance Hall 270 580
Factory 330 670
Bowling Alley 510 940
Factory 510 940

Notes

  1. Tabulated values are based on 78F for dry-bulb temperature.
  2. Adjusted total heat value for sedentary work, restaurant, includes 60 Btuh for food per individual (30 Btu sensible and 30 Btu latent).
  3. For bowling figure one person per alley actually bowling, and all others as sitting (400 Btuh) or standing (550 Btuh).
  4. Use sensible values only when calculated ventilation to remove heat.