How do I remove broan QS1 fan blade - Broan-NuTone Kitchen Ranges

There should be a set screw.

There are a number of YouTube videos that show how to replace the motor assembly on a Broan bath fan. Once you have unplugged the fan and removed the motor mounting plate you will have easy access to replace the blower wheel and/or the motor assembly.
Just go to You Tube and search on Broan

An old elecricians joke says "do you know why it hums? It dosn't know the words" Al kidding aside ,have you checked to see how free the fan blade is? The should spin very freely. It kind of sounds to me like it may be having a hard time comming up to full speed. You may try some graphite lube on the motor. If I recall Broan has a lifetime garrentee on the motor. You might just want to repace it if I am correct.

the fan should come right off. they screw on,- or they have a set screw,- or they have a clip,- or sometimes if they are plastic they just pull off. this is all assuming that you can get to the fan.

You need to balance the blades by adding weight to one or more blades so they all weigh the same. Stores sell a kit with stick-on weights.

SOMETHING IS HITTING THE FAN BLADE

check bolt holding fan is tight

The fan blade can be removed from the shaft. You just need to pop the lock washer off and pry the fan blade. You most likely will not be able to remove the fan blade without damaging the blade. You can buy the replacement fan blades online. The part number is 5901A000. Here is a blog on the entire replacement motor assembly. http://nutoneproducts.typepad.com/nutone-products/2009/08/nutone-0695b000-replacement-bath-fan-motor-for-model-qt80.html

Check the fan blades and see if it's being restricted.Another method is remove the fan blade turn the unit on and see if it spins if it doen'nt tap the motor gently and see if turns.If this works the motor brushes are worn

check these causes fan blade brackets,fan blade for cracks, any grease on blades.