iPad wont boot after screen replaced

Who did the replacement? If the screen was replaced due to a drop, there may be some internal damage or loose connection.

Some iPad users have been able to revive their dropped iPad. Turn the iPad over and give it a HARD SLAP on the back. May take several slaps.

dropped iPad

https://discussions.apple.com/thread/4474708?tstart=30

Try this - Reset the iPad by holding down on the Sleep and Home buttons at the same time for about 10-15 seconds until the Apple Logo appears - ignore the red slider - let go of the buttons. (This is equivalent to rebooting your computer.) No data/files will be erased.

What to Do When Your iPad Won't Turn On

http://ipad.about.com/od/iPad_Troubleshooting/ss/What-To-Do-When-Your-Ipad-Wo-No t-Turn-On.htm

iOS: Not responding or does not turn on

http://support.apple.com/kb/TS3281

iPad: Basic troubleshooting

http://support.apple.com/kb/TS3274

 Cheers, Tom 😉

Take it back to where you had it "fixed" and have them fix it again.