Record what happens
Note the thermostat model, selected mode, room and target temperatures, and messages. Does the indoor fan run? Does the room gain heat over time? Save the displayed information.
Tell the provider how you concluded auxiliary heat works. An AUX label and confirmed room warming are different evidence. Avoid switching repeatedly between modes to test it.
Do not open the thermostat, move wires, bypass controls, or repeatedly reset a breaker.
Request an actual backup test
Have the technician identify the backup heat type and what emergency mode should do here. Ask whether the thermostat supports that function and whether the configuration matches the equipment instructions.
The visit should establish whether the backup source receives the correct call and delivers heat. A blowing fan does not answer that question.
If backup components, a circuit, or an electrical supply issue are involved, confirm which qualified provider will assess them. Ask who coordinates any separate electrical work.
Request the actual finding and correction, rather than a menu change without an operating check. A system-specific test should show the intended backup sequence after repair.
Keep the waiting plan clear
If normal heating still works, ask which owner operating mode is appropriate while waiting. A visible menu option is not a verified fallback.
If the home cannot maintain needed heat, arrange prompt service and another heated place if necessary. Include vulnerable occupants and freezing risks in that plan with the appropriate provider.
Your next step is to send the thermostat information and observations with a request to test both auxiliary and emergency operation. Ask for the documented result before depending on emergency heat during the next failure.