How many zones can the Vista 20P support?

The Vista 20P has 8 hardwired zones built into the panel itself, and can support an additional 40 wireless zones through the use of a wireless receiver -- for a grand total of 48.

Honeywell has a variety of wireless receivers to meet your specific zonage needs. The 5881ENH can support an unlimited number of zones (meaning the full 40, in the Vista 20P's case). The mid-range 5881ENM receiver can support 16 zones, and the 5881ENL can support a maximum of 8 zones. When choosing the right receiver, it's important to access the future needs of your system. If you are planning to add more devices in the future, you want to make sure you have a receiver that can support those extra zones when the time comes.

The 6160RF alphanumeric keypad is also a viable option for adding zones because it has a built-in 5881ENH receiver plus advanced keypad features that allow for more intricate zone programming.