Thermostat display is on but does not respond to touch or button presses.

Safety warning: Turn off power to the thermostat circuit before removing it from the wall.

• 1. Power cycle:
  • Turn off the HVAC breaker for 2–3 minutes, then restore power.
• 2. Remove and reseat thermostat:
  • Pull the thermostat off its base and inspect the connector pins.
  • Reinstall firmly and check for response.
• 3. Factory reset (if possible):
  • If any hardware reset button is accessible, perform a reset per Lennox instructions.
• 4. Replace thermostat if still unresponsive:
  • The touchscreen assembly is likely failed and requires thermostat replacement.