Unit stops with F8, sometimes after long continuous operation

Safety first: Turn OFF the unit and allow any ice on the indoor coil to melt.

Steps:

• Clean filters: Ensure filters are clean and properly installed.
• Increase fan speed: Use a higher fan speed setting to improve airflow.
• Adjust set temperature: Raise the cooling setpoint a few degrees to reduce overcooling.
• Check for blocked vents: Ensure supply and return air paths are not blocked.

If F8 recurs frequently: The evaporator sensor or refrigerant charge may be incorrect; professional service is recommended.