We have a one year old Hampton Bay 3 speed fan without a light. The remote battery was changed and it worked fine. Now it will not turn on even when we change speeds manually and then try to turn it on with the remote. Can you override the remote and just turn it on with the chain?

Yes, just open the fan canopy, remove the remote receiver, and wire the fan as you would without a remote:

http://www.ceiling-fans-n-more.com/ceiling-fan-wiring.php