Can a LYNX Touch be a keypad for Vista 15P, 20P, 21iP?

The Honeywell LYNX Touch is not compatible with the Honeywell VISTA-15P, 20P or 21iP, but probably not for the reasons you're thinking.

The LYNX 5100 cannot be used with the Vista 15P/20P/21iP, because both are actually the same thing, alarm control panels.

Generally, the confusion comes because the Honeywell L5100 is not just a control panel, but also a fully functioning alarm key pad as well. It's basically a fully contained alarm system in one consolidated unit.

So there, you cannot buy a LYNX Touch to serve as your keypad to your Vista series panel. If you're looking for a touchscreen Advanced User Interface (AUI) for your Vista series panel, we'd recommend the Honeywell Tuxedo Touch WIFI.

It will give you all the cool features you're looking for in a LYNX Touch panel, including home automation, but will work with the Vista 15P, Vista 20P and their big brother, the Honeywell VISTA-21iP .