Unit shuts down or will not cool, display shows E2

Safety: Disconnect power to the Friedrich air conditioner before removing any panels.

Steps to address E2:

• Remove front cover: Take off the front grille and air filter. On PTAC and through-the-wall units, you may need to remove additional screws to access the evaporator coil area.
• Locate the evaporator sensor: This thermistor is usually clipped directly to the evaporator coil tubing or fins near the center or outlet side of the coil.
• Check mounting and condition: Ensure the sensor is firmly clipped to the coil and not hanging loose. A loose sensor can cause incorrect readings and E2. Re-clip it securely if needed.
• Inspect wiring: Follow the sensor wires back to the control board. Look for cuts, abrasions, or signs of overheating. Reseat the connector on the board.
• Test resistance: With the unit unplugged, disconnect the sensor and measure resistance. Compare to the service chart for your model. If the reading is open, shorted, or far out of range, replace the sensor.
• Replace sensor: Install a new Friedrich evaporator thermistor, routing the wires as originally installed and securing them with clips or ties to avoid contact with the fan or sharp edges.
• Control board check: If a new sensor does not clear E2, the main control board may be defective and require replacement.

Note: Do not bend or puncture the refrigerant tubing while working around the coil.