Which channels can be used in a Wi-Fi connection (2.4GHz band) to connect with a wireless router?

From 1ch to 13ch are available.

NOTE: 12ch and 13ch are available depending on your TV model, TV software version and region.
For TVs released in and before 2017, update the TV to the latest software.  
For how to update, refer to: How to perform a software update.

To reduce interference from other devices, we recommend setting the channel of the wireless router to Auto.
If your TV is the only device that cannot connect to the wireless router, the channel setting of wireless router could have been set to 12ch or 13ch. In this case, select another channel. To reduce the interference from other devices, it is recommended to set the channel settings to 1, 6, or 11ch.

NOTE: For details on how to set the channel, refer to the instruction manual or contact the manufacturer of the wireless router.