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508Wi-Fi not set up

Cross-checked Power off, standard tools

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

Related diagnostic guides

Guide · Thermostat

Thermostat setpoint changes by itself

Most 'ghost' changes come from features, not faults: a program schedule resuming after a temporary hold, learning schedules, eco/away modes, utility demand-response events, or another person or app. Check the thermostat history before replacing it.

4 steps ~20 mineasy

Guide · Thermostat

Smart thermostat offline / Wi-Fi problems

Separate network problems (router, credentials, internet) from power problems: many smart thermostats switch the radio off when batteries or borrowed power run low. Read the brand's code first.

5 steps ~30 mineasy

Guide · Thermostat

Auxiliary heat runs too much or all the time

Aux heat should only help when the heat pump cannot keep up. Constant aux usually means wrong wiring/settings (aux on the heat pump terminal, emergency heat left on), big setback recoveries, or a heat pump that is not producing heat.

4 steps ~45 minmoderate