Remote Time Capsule Not Available for Time Machine

I use my Apple ID to access a remote Time Capsule (at another house). I can access the disk in Finder, but that disk doesn't show up as an option in Time Machine->Select Disk. How can I use the remote disk for Time Machine?

Details -

• Remote Time Capsule - About 4 years old - Firmware V7.6.4 (latest update for that model)
• I also have a local Time Capsule that works fine. Only remote Time Capsule disk doesn't show up in Time Machine->Select Disk
• Local Time Capsule - Latest model - Firmware V7.7.2