Will Konnected work for us?

We have an ancient (early-mid 1990s) non-functioning formerly monitored system, and I'd like to use the wiring to connect wired smoke/fire detectors to a central system with battery backup (yes, I know of the cautions about using Konnected for this -- I'd only use things that would function on their own). 

My problem is, I don't know enough about what I have to know what to look for or what questions to ask. 

I first need to find out, is this a low-voltage system (see attached pics)? I had always presumed as much but once I pulled down one of the old fire sensors, the wires don't look like low-voltage wires (not much low-voltage experience but I always thought they were really fine gauge wires).  Also, there are four wires going to the detector, but I expected one to be white, and they're all red. 

Also, on the old keypad, it shows just one zone for "fire." Since we don't plan to attach any of the old security sensors (most are no longer there anyway), would this then just be a one-zone system? 

Finally, if this IS something we can potentially do, is there any suggestions anyone has based on looking at the current box and detector (both attached)? 

FYI I have decades of computer networking/network wiring and electrical experience, but this is all making me feel like a real dunce because I don't even know what questions to ask to get started.  All help and patience are appreciated. 

I have determined that these are Edwards 282-B heat detectors.