Noise Troubleshooting (Public)

If you have a fan that is perceived as noisy, start troubleshooting by answering the following questions. 

1. Describe the noise you are hearing (grinding, whining, clicking, frequency, etc.)
2. When was the fan installed?
3. Has the noise been present since installation, or did it start later? If later, when?
4. How many fans are on site? If more than one, how many are the same model? If there are multiple of the same model, are they all making the same noise?
5. At what speed(s) and direction(s) is the noise heard?
6. Can you send us a video of the noise and verify that the noise in the video is an accurate representation of what is heard on site?

Noise Types

Clicking: No/not enough moly plate was applied to the struts during installation. The struts will need to be lubricated using the provided moly plate. Apply the provided lubricant in 4 spots on the top and 4 spots on the bottom of each strut as indicated. Each line of lubricant should be in a groove of the strut, starting at the tip of the strut, approximately 1”-1.5” long and spaced as indicated. The lubricant should reach the top of the groove. It is not necessary to use the entire tube. 

Whistling: This may be related to loose end caps on the blades. Try tightening them or removing them entirely to verify if the noise persists. It may be possible to use electrical tape to tighten the fit, but new end caps may be necessary if they are too worn out to fit securely into the blade.

Grinding/Whining:

1. Older gearbox fans (non-integral): Speak to Technical Support for best practices, as these will vary depending on the age and model of your fan.
2. Current gearbox fans: 

• Ensure everything is installed correctly (including removing the breather plug and sensor plug) and that all hardware is torqued to the specifications outlined in the installation manual. Speak with Technical Support for further troubleshooting.
• Ensure that the noise is abnormal. This is most easily done by verifying if noise has been present since installation and if there is more than one identical fan model on site making the same noise.  Use the spec sheets (located here) to confirm if the sound level is outside of specifications. 

3. Direct-Drive Fans:

• Verify that the blade size and motor calibration were done (AVDX only). Reset the blade size and perform another motor calibration. If the fan has a bottom cover, run the fan without the bottom cover. Speak to Technical Support for further troubleshooting.
• Ensure that the noise is abnormal. This is most easily done by verifying if noise has been present since installation and if there is more than one identical fan model on site making the same noise.  Use the spec sheets (located here) to confirm if the sound level is outside of specifications. 

Frequency: Verify that everything is installed correctly. Use the spec sheets (located here) to confirm if the frequency is outside of specifications. Speak to Technical Support to verify that the fan is programmed correctly.

Note on frequency noise: During normal fan operation, a high-pitched noise may be heard depending on the environment the fan is located in. This pitch is known as the carrier frequency. The carrier frequency is present in every motor/VFD application and is not limited to MacroAir or HVLS fans in general.

It cannot be eliminated entirely, but can be less audible in certain applications due to the type of frequency selected, the type of motor, and/or the type of environment the fan is installed in.

We have fan lines with different motor types that operate at a higher (less audible) carrier frequency, while there are other motor types that will sound louder due to the motor design and the carrier frequency that is necessary to run that motor at an appropriate temperature.

There are different ways to tune a motor and carrier frequency. Less noise (higher frequency) generally means that the motor will run hotter. More noise (lower frequency) will cause the motor to run cooler. Tuning more towards noise reduction would result in increased motor temperatures, which would shorten the life of the motor and could result in a premature failure. We tune our motors for the optimal balance of noise versus motor heat to ensure that the motors last the standard 5-10 years of our electrical warranty and beyond.