Fix the inconsistent 3G data on Nexus 5

If you have a Nexus 5 and you are depend on your 3G data while travelling (on roaming), you might have noticed that the data connection get stuck every now and then. The data connection does not come back until you turn it off and turn back on the data to switch. Sometimes you might even have to reboot the phone. This issue may not occur when you are actively browsing on your phone however, waking the phone up from standby shows the issue more visibly. I noticed this issue twice a week back and was quite annoyed with the manual work I had to do to restore all the connections until I bumped into the solution.
 

The reason
The Nexus 5 unlike its predecessor, comes equipped with LTE. The LTE radio is enabled by default in Nexus 5. It looks like the Nexus 5 tries to search for data connection on LTE but since it cannot find any signal for data connection, it gets stagnant.
 

Solution
Many places where I visit there are no LTE data /signal available. Switching the preferred network type to 3G from LTE helped get a consistent 3G signal without interruption. You can find the setting in Android 4.4.2 in
Settings -> More -> Mobile Network Settings -> Preferred network type -> 3G