I just installed the ELK-M1XRF2G and am trying to enroll some older GE/ITI devices. I am pretty sure they are crystal rather than SAW but can't be 100% since I am not able to find any info on the model numbers. I pushed the TEST button on one of the fire detectors and it went off, and was recognized by the Elk, however it instantly said FIRE TROUBLE and no matter what I did, I was unable to clear the fault from the keypads. I entered my code 2 times, maybe the zone silent, etc. The only way to clear was to turn off Elk and turn it back on. Then after a few mins it would give the fault again. I even replaced the fire detector batteries. I am not sure if it is setup in Elk wrong, or it is indeed a SAW device that happened to enroll but isn't working correctly.