Programming Element TV with remote.

I had to have Comcast come out and replace my dvr box because it was not working.  I had called a few days before to talk to customer service and they reset me box remotely but that didn't fix the problem but it stopped my remote from working the tv.  The technicion hooked up my new box today but can not get my remote to control my Element tv.  He tried making it search for the code by using the channel button and it gets to a code and powers down but will not power back on.  Please help because two remotes is annoying and this was working before.