Electronic Alarms and Home Security Devices - Getting Fire Detectors to Interact

Hi,
Our house was hardwired for smoke detectors/alarms. Recently I replaced the basement and ground floor smoke detectors with Kidde Smoke detector/CO detector combo unit. I also replaced the two floor units with new Kidde smoke detectors. However, when I test the basement and ground CO/Fire units, they interact (both beep) however the top two Kidde Smoke detectors do not beep. The two Kidde smoke units dont even beep between each other.

I placed the CO/Smoke combo detectors in the basement and ground floor because of obvious CO coming from the furnace/gas range. The combo units are expensive $50 each.

is there a way I can get the fire detectors to interact with the existing units (all 4 beep in case of an alarm?)

Thanks!

I'm gonna go out on a hunch here.

Are the two that do not interact on the same electrical circuit, meaning are they interconnected with the same electrical wires?

Find the circuit breaker that controls them and shut it off. Iff all the detectors are on the same circuit, like they should, all of them should loose power.

That's my thought too, they have to share an interconnect circuit for all to be triggered. That's what that third wires is for, and they all have to be connected to a common circuit.

The whole was wired before we bought it. It doesn't make sense for them not to be connected, but I will reset the fuse box this weekend to see.

Generally speaking, it's ok to mix and match devices?

Many thanks!

Since you are using all products from the same maker, they should interconnect (have you checked something as simple as the wire nut connections at the junction boxes?)

You can check the Kidde site to be sure (http://www.kidde.com/utcfs/Templates/Pages/Template-53/0,8062,pageId%3D4431%26siteId%3D384,00.html), but I would check your connections on those interconnect wires, especially if the old detectors worked correctly, before. (The previous detectors _did_ interconnect, didn't they?)