York ducted or packaged AC shuts down and displays E1 on the wall thermostat or indoor unit display

Safety first: Turn off power at the outdoor disconnect and the indoor air handler breaker before touching any components. High pressure conditions can be dangerous.

• Check outdoor airflow: Inspect the York condenser coil for dirt, cottonwood, or debris. Gently hose from inside out (power off) and straighten any badly bent fins.
• Verify outdoor fan operation: Restore power and observe the outdoor unit. If the compressor runs but the fan does not, the fan motor or its capacitor may be faulty. Shut power off again and test/replace the fan capacitor and motor as needed.
• Inspect high‑pressure switch: Locate the high‑pressure switch on the liquid line or discharge line in the York condensing unit. Check for a manual reset button (if equipped) and press it once with power off. If it trips again, do not keep resetting—find the cause.
• Check for airflow restrictions indoors: Replace dirty return air filters, open closed supply registers, and ensure the blower wheel is not caked with dust.
• If system is overcharged or pressures are abnormal: A licensed HVAC technician must connect gauges, verify charge, and correct refrigerant level according to York specifications.