Digital Summit upright freezer beeps and displays E1; temperature reading may be blank or show dashes.

Safety first: Unplug the freezer from the wall outlet before removing any panels or handling wiring. Use insulated tools and avoid working on a wet floor.

Steps to check and address E1:

• Power reset: Unplug the freezer for 5 minutes, then plug it back in. If E1 returns, continue with diagnosis.
• Locate the cabinet thermistor: On most Summit uprights, the cabinet temperature sensor is behind an interior liner cover or clipped to the evaporator cover inside the freezer compartment. Remove the interior panel screws and gently pull the panel forward.
• Inspect the sensor and wiring: Look for a small bullet-shaped or cylindrical sensor with two wires. Check for cuts, pinched wires, or ice buildup around the sensor. If the sensor is encased in ice, carefully defrost with a hair dryer on low, keeping it away from plastic surfaces.
• Check the connector: Follow the sensor wires to the plug connection. Ensure the connector is fully seated and free of corrosion. Reseat the connector several times to clean the contacts.
• Test the thermistor (if you have a multimeter): With the freezer unplugged, disconnect the thermistor from the harness and measure resistance across the two leads. Compare to a typical NTC curve (for many Summit sensors, ~5–10 kΩ at room temperature). If the reading is open (infinite) or shorted (near 0 Ω), the sensor is bad.
• Replace the thermistor: If damaged or out of spec, install a new Summit-compatible cabinet thermistor. Route the new sensor along the original path, avoiding sharp edges and moving parts. Reconnect to the harness and reinstall the interior panel.
• Restore power and test: Plug the freezer back in and allow several minutes. The E1 code should clear and a normal temperature should display. Monitor temperature for several hours.

When to call a technician: If the thermistor and wiring are good but E1 persists, the main control board may be faulty and should be diagnosed or replaced by a qualified technician.