New upgraded First Alert Zcombo will not work with Smart things

[jkp]

I am pretty certain performing a manual test on any Smoke Detector will not register in SmartThings. Or at least that use to be the norm years ago.

Smoke CO detectors don't notify me when I test them

The “test” function does not trigger Smart Home Monitor. If you want to end-to-end test Smart Home Monitor for Smoke, then you need to actually waft some real smoke (or “canned simulated smoke” - available at hardware stores) to the detector. Personally I just carefully light some paper (after soaking most of it in water).