Dehumidifier will not run, display shows E1 and keypad does not respond to button presses.

Safety first: Unplug the dehumidifier from the wall outlet before removing any panels. Do not work on the unit while it is connected to power.

Steps to check and correct:

• 1. Power reset: Unplug the unit for 5–10 minutes, then plug it back in. Sometimes an E1 code is a temporary communication fault that clears with a reset.
• 2. Inspect control panel connections: Remove the front grille or top cover (depending on model) to access the control panel. Locate the flat ribbon cable or harness that runs from the keypad/display to the main control board. Ensure it is fully seated at both ends and not pinched or damaged.
• 3. Check for corrosion or moisture: Carrier dehumidifiers often operate in damp basements. Look for green/white corrosion on the connectors. If present, gently clean with electronic contact cleaner and a soft brush, then reconnect firmly.
• 4. Examine the UI board: Look for burn marks, cracked solder joints, or water damage on the keypad/display board. If the board is visibly damaged or E1 persists after reseating cables, the UI board is likely faulty.
• 5. Inspect the main control board: Access the main PCB (usually near the compressor side). Check for burnt components or swollen capacitors. If the UI board looks good but E1 remains, the main control board may not be processing keypad signals.
• 6. Replace faulty board: If you identify a failed UI or main control board, order the correct Carrier replacement by model and serial number. Transfer any wiring one connector at a time to avoid miswiring.

When to call a technician: If you are not comfortable opening the cabinet or working around electronic boards, or if both boards appear fine but E1 persists, contact an authorized Carrier service technician.