Customer Support Hub

COS-QB48 FAQ

Q: What if my question isn’t listed here?

A: General FAQs

Q: How do I set the time of day on my range hood (COS-QS75, COS-QS90, and COS-QS48 only)?

A: To set the clock on your range hood: 

  1. With the unit powered off, press the timer button.
  2. Use the + and – buttons to adjust the hours.
  3. Press the timer button once more.
  4. Use the + and – buttons to adjust the minutes.
  5. Allow the unit to sit for 3 seconds without using any controls for the clock to finish setting. The clock can only be used in 12h format.

Q: How do I set a shut-off timer on my range hood?

A: To set the shut-off timer on your range hood (digital units only):

  1. Turn the fan on and set to the desired speed.
  2. Press the timer button.
  3. Press the + and – buttons until the desired shut-off time is displayed.
  4. The timer can be set up to 15 minutes.
  5. The fan will shut off automatically when the timer ends.

Q: How do I change my clock to/from a 24h format?

A: Your range hood does not have the ability to change time formats. 

Q: How do I convert my unit to ductless?

A: To convert your unit to a ductless operation and recirculate the air back into the room:

  1. Purchase the necessary carbon filter kit found online at www.cosmoappliances.com/product-category/parts-and-accessories/range-hood-parts/filters/. This filter is not included with your purchase and must be purchased separately.
  2. Remove the stainless baffle filters on your range hood.
  3. Remove the 6 screws on each motor cover and remove the motor covers.
  4. Replace the motor covers with the mounting rings included with the carbon filter kit.
  5. Install the carbon filters by pressing them against the mounting rings, one at a time, and twisting clockwise. They will create a tight seal.

Q: Can I change the lighting on my range hood?

A: The QS75, QS90, QS48, QB75, QB90, and QB48 can be changed to any GU10 bulb with less than or equal to 2W max. We also carry 3500K replacement lights online at www.cosmoappliances.com/product-category/parts-and-accessories/range-hood-parts/lights/. These will change the color temperature of your range hood to an orange-white that may better match the lighting already present in your kitchen. They are the same overall brightness as the lights included with your unit.

Q: Why is my range hood making a loud noise when I turn on the fan?

A: The most common cause of this issue is shipping tape being present on top of the damper flaps, preventing them from opening properly.

  1. 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.