When I changed the battery in my remote, I could not get the fan to do the three speeds. It will only do high speed

Try changing the batteries if the remote worked before you changed batteries there is nothing wrong with the remote - just the batteries. Sometimes batteries can do weird things to remotes if they are the least bit drained - even out of the package.

I tried that and now the remote doesn't work at all. I'm getting not read outs for temp etc.