I have Cyangenmod 10.1.3 installed on my Xperia Z. When I tried to download Cyangenmod 10.2-20131101 nightly build in my phone's settings, no error but it silently failed after some time. I tried again but the problem persists. 

Any idea what went wrong? 

Am I supposed to download the zip file, copy it to my phone and boot into recovery mode to do a manual installation?