Wiring Nest Protect and another brand together

[Walt83]

I'm thinking of making a change to our setup. The house we bought has wired smoke detectors. I replaced some with Nest and realize that creates some risks.

I'm thinking of putting the others back in place and connecting adding a short wire from the wire nut to an adjacent Nest, allowing me to monitor each floor and key bedrooms while not losing the interconnected solution covering the whole house. 

I don't see why this wouldn't work, but figured I'd check with this group.

Thanks for any help you all can offer!

Walt 

[David_K]

This isn't supported I'm afraid. If one of your Nest Protects sounds an alarm, your conventional detector will not sound unless it also detects the issue and vice versa if the conventional detector senses something that Nest Protect hasn't yet.

Each manufacturer uses proprietary detection algorithms meaning there’s no industry standard. What that means in practice is if alarms from different manufacturers were to be connected together, they may not warn you properly in an emergency. The NFPA actually prohibits the connection of alarms from different manufacturers without special testing. As far as I'm aware, there's no manufacturer that sells a detector that is designed to interconnect with a device from a different manufacturer and some manufacturer's even state in their documentation not to try to connect their device to that of a different manufacturer.

[Walt83]

Not sure I follow. 

In my case we have kiddie hard wired with an extra wire for communication. 

If I tap into the power wouldn't I have two independent systems, all running off the power from the Kiddie system.

I get this means two systems. For the people in the house, the Kiddie system would provide safety to our family, and the Nest would provide redundancy and remote notifications.

I have four Nest protects, one in the basement, first floor main living area, 2nd floor main hallway and in the master suite.

In this plan I'd have Nest and Kiddie side by side, both using the power from the initial kiddie installation.

Are you saying the two systems wouldn't work independently as designed sharing the power source?

[David_K]

Ah you're simply referring to hardwiring the Nest Protect to power, not trying to interconnect the two systems. Google has step by step instructions on connecting to your system wires.

Install Nest Protect - Google Nest Help