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Hello, my name is ***** ***** I am a professional here at Just Answer. I have noticed that your question was not getting a response and thought I would see if you still need help with this.I apologize for the delay and I hope I can still assist you with this here.The first thing you want to do is to make sure the battery will hold a load and the charging system is charging at the correct amount with the engine running, a normal working alternator charge rate is right at 14 volts with the engine running. If the battery checks okay as well as the alternator then you likely have a draw which means something is not shutting down when the key is off and that means you are going to need to perform a battery draw test. I have enclosed the steps to check for a draw in the link below, copy and paste the link to your browser to open and view them.https://dl.dropboxusercontent.com/u/104923897/Draw%20test%20Oct%209.pdf
Have you verified that the new alternator is charging when its on the car, normal engine charging voltage should be right at 14 volts with the engine running.
Okay if the alternator is charging the battery with the engine is running and the battery is still going dead on you then you are going to need to perform the battery draw test I sent you in my first post.
You can pick one up at any parts store for about $10.00
Its called a 12 volt test light.
See this linkhttp://www.autozone.com/test-scan-and-specialty-tools/test-light