Carel AL69

What does Carel AL69 mean?

AL69 is the Driver 2 LAN Disconnected alarm on the Carel Standard Air-conditioner (030221426). The pCO controller has lost communication with EVD driver 2 on the pLAN network for more than the allowed timeout. Without a network connection, driver 2 cannot receive setpoint and control commands from the main controller, and circuit 2 may shut down or revert to digital input control only.

Symptoms

• AL69 displayed on the controller.
• Driver 2 NET LED on the EVD board is off or flashing, indicating a communication fault.
• Circuit 2 compressor may shut down or operate at a fixed valve position depending on digital input status.
• Alarm relay activates per configured relay output assignment.

Common causes

• pLAN network cable between the pCO controller and EVD driver 2 disconnected or damaged.
• Incorrect pLAN network address configured on driver 2 or the controller.
• EVD driver 2 has powered off or lost its supply voltage.
• Network communication cable too long or without proper termination.
• Electromagnetic interference from nearby variable speed drives corrupting the pLAN signal.

Diagnostic steps

1. 01

   Inspect pLAN cable to EVD driver 2

   Check the tLAN/pLAN cable between the pCO controller and EVD driver 2. Reseat both connectors and inspect the cable for pinching, cuts, or loose terminal screws.

2. 02

   Verify EVD driver 2 power supply

   Confirm driver 2 is powered by checking its indicator LEDs. Measure supply voltage at the driver 2 terminals and verify it is within the specified range for the driver model.

3. 03

   Check network address configuration

   In the EVD driver 2 service menu, verify the network address is set correctly and does not conflict with other devices on the pLAN bus. Consult the Standard Air-conditioner application installation documentation for required addresses.

4. 04

   Check cable routing for electromagnetic interference

   Ensure the pLAN cable is not routed adjacent to high-power conductors, inverter drive cables, or other electromagnetic interference sources. Reroute and shield if necessary.

5. 05

   Power-cycle driver 2 and monitor recovery

   After correcting wiring or address issues, power-cycle EVD driver 2. Monitor the pCO alarm list to confirm AL69 clears and driver 2 communication is restored.

When to call a professional

If AL69 persists after verifying all wiring, power, and address settings, the EVD driver 2 board or the pCO input/output expansion for the LAN port may be faulty. Board-level replacement and re-commissioning of the network connection require Carel-authorized service personnel and manufacturer access credentials.