A: There are many reasons that a fan may not perform as expected. Before we look at these, we must first understand what acceptable performance entails.
AMCA Publication 200 states that a fan in a ventilation system should expect an airflow tolerance of +/-7.5% CFM. For example, a fan 1000 CFM fan should provide an airflow rate of 925 to 1075 CFM when properly installed. If the CFM is outside this range, it could be a result of variances in static pressure in the system or a mechanical problem with the fan.Common causes include:
A: AMCA stands for Air Movement and Control Association International (AMCA). It is a not-for profit international association of the world’s manufacturers of fans, louvers, dampers, air curtains, air flow measurement devices, ducts, acoustic attenuators and other air system components. AMCA operates its own laboratories in Chicago and Singapore, and uses a licensed independent laboratory in Seoul Korea to test and certify the ratings and regulatory compliance of member and non-member products. AMCA develops industry related test standards for air movement and control products while independently certifying product performance to ensure reliable and accurate product performance. For more information about AMCA please visit amca.org
A: A sone is an internationally recognized measurement of loudness, or how loud a sound is perceived. A unit with double the sone value of another would be perceived as twice as noisy.
A: Static Pressure or hydrostatic pressure is the resistance to airflow (friction) caused by the air moving through a pipe, duct, hose, filter, hood slots, air control dampers or louvers. This resistance reduces the performance of the fan.
A: Yes! Canarm's Delair Fan Selection Software has a variety of tools to make choosing the right fan or blower easy. For more information, and to download Delair, click here.
A: Yes, many models can be ordered without motor and drives (pulley & belt).
A: Motor manufaturers provide detailed wiring instructions on labels attached to the motor. The wiring diagrams are not in our user manuals because they cover multiple configurations which may use different motors.
A: This typically means there is an electrical problem. If you do not hear a hum or other noises from the motor, try the following:
A: Over time certain parts on a fan can become worn or loose and can cause unwanted noise. Worn parts usually need replacing, but loose hardware can be tightened. Try the following:
Note: If there is a humming sound this could be caused by the use of a solid state variable control. If this is the issue, try a different fan control. For a list of controls that Canarm offers, click here.
A: Excessive belt tension is the most frequent cause of bearing wear and resulting noise. Belt tensioning methods differ depending on the fan/blower series. The user manuals detail the tensioning methods for each series and can be found here or under the resources tab in the toolbar above.
A general rule of thumb is to have a 3/4” of deflection mid span under medium finger pressure (2-3 lbs) for every foot of span for proper belt tension.
A: Proper pulley alignment is critical. Misaligned pulleys may cause fan vibration, noise and/or premature wear.
To align the pulley, adjust the position of the motor on the motor bracket or motor platform until correctly aligned as shown above. A straight edge across the face of the driven pulley should be parallel to the belt once proper alignment has been achieved.
Note: Adjustments to variable pitch pulleys require pulley re-alignment.
A: The drive pulley (motor pulley) is a variable pitch pulley. Adjusting the pitch diameter will change the speed of the blower within the adjustment range of the pulley. To adjust the pulley do the following:
A: To replace a belt drive motor, first check the user manual for the motor. If you are unable to find instructions, follow these steps. Keep in mind that not all motors are the same and some instructions may not apply.