Were the boxes resealed or did they appear to be the original factory seal on the boxes? I ask because HD has been overly generous in accepting back products and some customers have been dishonest in returning them.
I bought a Hampton Bay ceiling fan from HD some years ago and it made a clicking sound when I installed it. Unusual! I opened it up and something fell out; never did find what it was. I put it back together and it was fine; I have been using it for years. When I thought back on it, I recalled that the box had been resealed. Some customer had probably returned it without telling HD that it was defective, and they restocked it.
In your case someone may have installed them and used light dimmers on them. That will make the motor hum, and there is no fix for that. A dishonest customer may have taken them back and been unwilling to tell that he had destroyed the motors through his own stupidity, just to get his money back.
But if the boxes were factory sealed and the parts bags inside were factory fresh, then you have a couple factory defective fans.
In either case you should take them back. For gosh sakes, tell them that they are defective and stick some masking tape on the boxes and write defective on that. If you feel it has been too long waiting, that in itself is no crime. You can take them back with no receipt and get a store credit card, which you can then use to get a couple new fans.
you should also take into consideration that these fans were sitting for a while before you got to them, so you will just need to let them run for a while. once they get going they should be fine. if you have any questions call the 800 number in the manual.
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