Is a Honeywell L7000 Compatible with a Honeywell L3000?

No, a Honeywell L7000 is not compatible with a Honeywell L3000. These are both separate alarm control panels. You will never have more than one alarm control panel in the same security system setup. But you can add an external keypad to provide a second point of access for the system.

An alarm control panel serves as the central hub for a security setup. All of the sensors report to the panel when they are activated. The panel is also the piece of equipment that what will send out a signal when an alarm occurs. And since the L7000 and L3000 are both wireless all-in-one (AIO) panels, they also serve as the primary controller for the security system. This means that the user will interact with these panels for regular actions like arming and disarming. As such, the panel is perhaps the most important part of a security system.

The thing is though, there is only one alarm control panel per security system. No more, no less. You cannot add a second alarm control panel to a security system. Likewise, you cannot have a security system without an alarm control panel. It's possible to have multiple security panels in the same building. They can even be enrolled with the same uni-directional sensors. But they will still be considered separate systems.

It's understandable why a user might think the L7000 would work with an L3000, or vice-versa. After all, they are both manufactured by Honeywell, and a user might think one system could serve as a secondary keypad to control the other. But this is not the case. There is absolutely no way to have the L7000 and the L3000 interact on the same security network.

Fortunately, you can add a secondary on-site controller to either of these systems by adding an external keypad. And since these are both LYNX Systems, they can use the same wireless keypads. A great keypad to use for either system is the Honeywell 5828. Please note that you will need to program the House ID for the L7000 or the L3000 to program the 5828.