Indoor unit shows E8 and system shuts down, often after running for a short time

Safety: Turn off power at the outdoor disconnect. Do not attempt to open the refrigerant circuit yourself.

Steps:

• Clean condenser coil: Remove top or side panels as needed and gently wash the Comfortmaker condenser coil from inside out with water. Avoid bending fins.
• Check outdoor fan: Restore power briefly and observe if the fan starts and runs at full speed. If not, suspect a failed fan motor or capacitor. Turn power back off before testing.
• Inspect fan capacitor: Test the outdoor fan capacitor with a meter and replace if out of spec.
• Clear obstructions: Ensure at least 24 inches of clearance around the unit and no hot exhaust blowing onto it.
• Verify filter and indoor airflow: Replace dirty filters and ensure all supply/return registers are open to prevent high head pressure.
• Reset: After cleaning and checks, leave power off for 10–15 minutes, then restore and test operation.

Technician required: If E8 persists after airflow issues are corrected, a refrigerant charge or TXV problem is likely and must be handled by a licensed HVAC technician.