If your Sub-Zero 690 refrigerator won't turn on after leaving the door open, follow these steps to reset it potentially:
1. First, make sure the refrigerator door is securely closed. Check for any obstructions that might prevent it from closing properly.
2. Locate the circuit breaker or the power outlet that supplies electricity to the refrigerator. Turn off the circuit breaker or unplug the refrigerator from the power outlet.
3. Wait for about 5 minutes to allow the refrigerator's electrical system to reset.
4. Plug the refrigerator back in or turn on the circuit breaker.
5. After restoring power, try turning on the refrigerator again using the control panel or power switch.
If the refrigerator still doesn't turn on, there may be a more significant issue, and you should contact Sub-Zero customer support or a qualified technician for further assistance and diagnosis.