Assuming you have a new router you will need to enter new wireless password using Settings on screen when connected to NowTV box.
You should see Network then Set Up new Wi-Fi Connection.
Hi @jimobasa, who are you changing to ? If it is Virgin you may find it prefers 5ghz to 2 GHz. Basically though your box should be able to sign into any direct WiFi network. So if you move you can take your box with you. The box even works via a tethered connection 🙂