Customer Support Hub

COS-QB90 Motor Troubleshooting

My motor is making a loud noise while in use
  1. The most common cause of this issue is shipping tape being present on top of the damper flaps, preventing them from opening properly. To check that the damper flaps are working properly, follow the steps below: 
    1. Unplug your unit.
    2. Remove the ductwork from the top of the hood. 
    3. Pull on the damper flaps with your hands to make sure they are not stuck in place, and that any tape or other debris is removed from their path. 
    4. Remove the damper flaps one at a time and attempt to spin the fan with your hand, or using a long tool such as a screwdriver. 
    5. If the issue persists, please look for any other blockage in the duct, or any external dampers that are not opening properly.
  2. Feel for any abnormal vibration while in use. This can be a sign of an unbalanced fan.
    1. Unplug your unit.
    2. Remove the screws on each motor cover to reveal the fan blades.
    3. Wearing gloves, spin the fan blades manually to check that they are balanced properly. They should spin smoothly with no wobbling.
  3. Ensure that the correct duct size is being used according to the required specifications in the installation manual. If the duct size has been reduced, it will negatively affect both the suction power and noise level of the range hood.
  4. The grease filters may be clogged or dirty. 
    1. Thoroughly clean or replace the baffle filters.
  5. If the issue is not resolved, record a brief video of the sound and send it to support at staff@cosmokitchenproducts.com. This will allow us to properly diagnose your range hood and suggest any replacement parts if necessary.
My motor does not turn on, but all of the other controls work
  1. Check that the fan has not become jammed due to an obstruction:
    1. Unplug your unit.
    2. Remove the permanent steel filters on the bottom of the range hood.
    3. Remove the 6 screws on each motor cover to reveal the fan blades.
    4. Using protective gloves, spin each fan gently with your hand.
    5. If the fan doesn’t turn, contact a qualified appliance repair technician who can repair the motor(s).
    6. If the fan spins freely, contact support for a replacement motor/fan assembly.
  2. Check the connection for the blower motors:
    1. Unplug your unit.
    2. Remove the permanent steel filters on the bottom of the range hood.
    3. Remove the 6 screws on each motor cover to reveal the fan blades.
    4. Inspect the connection for the blower motor(s). If it appears loose or damaged in any way, first attempt to reconnect it.
    5. Contact support or a qualified technician for further troubleshooting and diagnosis if the connection is damaged and/or cannot be reconnected.
My motor is physically damaged
  1. Occasionally, the motor on this unit may arrive damaged from shipping or from an obstruction causing damage to the fan blade. 
  2. Fortunately, the motor is an easy part to replace and requires the removal of a few screws and a single plug.
  3. Contact support for a replacement motor/fan assembly and for further details on replacing the motor assembly.
My motor doesn’t seem to be pulling enough air
  1. The airflow on your unit is affected by many factors such as the unit’s CFM, the size of the kitchen, the number of doors or windows in the kitchen, the length of the ductwork, the number of elbows (i.e. bends) in the ductwork, the distance away from the cooking surface, etc.
  2. If your fan does not seem to pull air as efficiently as you would like, try holding a thin tissue up to the baffle filters while the unit is set to the highest fan speed. If the tissue is held up to the filters after you release it, the fan is working as designed.
  3. If the tissue falls easily, check that the ductwork has been installed properly: 
    1. Unplug the unit.
    2. Remove the ductwork from the top of the unit, first removing any chimney covers if applicable.
    3. Plug the unit back in, and try the tissue test again.
    4. If the fan holds the tissue without the ductwork installed, then there is an issue with the installed ductwork or another aspect of the installation. Contact a qualified specialist who can correct the installation and improve the fans efficiency. 
    5. If the fan still does not hold the tissue on high speed, contact support for additional troubleshooting and replacement parts under warranty, if applicable.