An already-high reading is not a new crossing
If a lamp should indicate that a room is warm, a threshold trigger can work perfectly and still do nothing when you enable it at an already-high reading. Home Assistant distinguishes a trigger that reacts to a change from a condition that checks the present value. Decide whether you want an alert once when the temperature rises, or a lamp that reflects the current state even after a restart. Those are different jobs.
Use a test helper and a harmless action
Make a separate test automation with a numeric helper as its input and a log entry or test lamp as its output. Use an above-25 threshold. Start at 26 before enabling it: no new crossing has occurred. Move to 24, then 26: look for a trace and the action. Move to 27: do not expect a second crossing while the value stays above the line. Record the value before and after each change and whether the trace exists. This checks the trigger without heating a room or changing a real controller.
Give startup reconciliation its own trigger
If the job is to restore the correct lamp state, add a separate Home Assistant startup path and evaluate the current value as a condition before acting. Sensors may not have a valid reading as soon as the system comes up; treat missing data as unknown and verify again after a valid reading is available. Test that path with a separate manual test event first, and observe the next planned restart instead of interrupting working automations. Keep the action idempotent: turn the indicator on rather than toggling it.
Decide from the trace
If 24 to 26 creates a trace but startup at 26 does not, fix the recovery path, not the sensor. If neither creates a trace, confirm the selected entity changes numerically and check that the automation is enabled. If there is a trace but no result, inspect its conditions and action before changing the threshold. Do not apply the test to a heater, alarm, or other safety-critical control.
References: Manufacturer or project documentation. Related: Handle unavailable readings separately from zero.
