Cause

If the hardware has been replaced or worn out, the physical flow rate will no longer match the stored software values. Leaking can occur if connections are loose or the internal tube is damaged.

Solution

Open the pump head and verify that the tube is perfectly aligned, not pinched, and free of tears. Ensure external tube connections are tight. After ensuring the hardware is correctly seated or after replacing any wear parts, you must perform a new calibration to ensure the software knows the exact flow rate of the pump.

Cause: Mechanical friction

Over time, salt creep, dust, or dried-out factory lubricant (on Doser 3 and Maxi models) can create friction that prevents the motor from turning smoothly. Alternatively, the pump head might not be seated correctly on the motor shaft.

Solution

Open the pump head. Clean all internal parts (rollers, turntable, and housing) with a lint-free cloth. Verify the head is pushed completely onto the motor shaft.

• For Doser 3 and Maxi models: Re-apply original GHL lubricant to the moving parts.
• For Doser 2 models: Ensure the head remains completely clean and dry — never use lubricant here as it will impair functionality.

Cause: Insufficient power supply

The Doser may be connected to a 12V power supply (e.g., from a ProfiLux) instead of the required 24V supply. The 12V unit fits physically but does not provide enough torque to turn the pumps.

Solution

Check the label on your power supply brick. Ensure it clearly states Output: 24V. If it says 12V, swap it for the correct 24V Doser power supply to restore full motor torque.

Cause

The pump configuration may be set to react to a Switch Channel or Level Sensor instead of its internal schedule, or the “Daymode” settings are preventing operation on the current date (e.g., set to specific weekdays or a day-interval that has not started yet).

Solution

In the pump settings via GHL Connect or GHL Control Center, verify that Dosing schedule below is selected in the “Pump reacts to” section. Additionally, double-check that the Daymode (weekdays or intervals) actively includes the current date.

Cause

When a Doser is switched from Standalone (SA) to Extension (EXT) mode, it stops following its own internal logic and schedules because it is now waiting for direct commands from a Master controller.

Solution

Verify the “Operation mode” in the General settings of GHL Control Center or GHL Connect. If the mode is set to EXT, you must program all dosing schedules on the Master device (ProfiLux or Master Doser). The EXT unit will no longer react to any schedules programmed directly on its own interface.

Cause

The pump is currently operating in Continuous Mode. To prevent configuration conflicts while the pump is running in a steady stream, the software locks these specific fields.

Solution

Briefly switch the pump mode to Automatic or Individual times. This will unlock the fields, allowing you to edit the speed or flow rates. Once adjusted, you can switch the mode back to Continuous Mode.

Cause

The software is ignoring the fill level calculations because monitoring is disabled, or the necessary alarm thresholds and triggers have not been configured correctly.

Solution

Ensure Switch off level monitoring is unchecked. Verify that a valid Minimum/Maximum threshold is set and that the Alarm when below min./Alarm when above max. option is actively checked in the container settings.

Cause

The Doser is not communicating with the Master controller over the PAB bus due to a cabling issue, or the device has not been properly assigned in the system.

Solution

Ensure the PAB cable is securely plugged into the correct PAB ports on both devices (do not plug it into the LAN port). Check that the EXT Doser has power.

• In GHL Control Center: Navigate to the System page and click Assign devices.
• In GHL Connect: Navigate to the System page, select Assign and configure connected PAB devices, and then click Assign devices.

Repeat the search to identify and assign the newly connected Doser to your Master device.

Cause

The Doser 2 hardware needs to be told that it is now driving Doser 3 pump heads, which requires a specific firmware version and a software flag to be set.

Solution

1. Ensure your Doser 2 firmware is at least version 1.55. If not, perform a firmware update.
2. Navigate to the configuration setting based on your interface and device type:
   • In GHL Control Center: Go to the System page, select/highlight the Doser (Standalone or EXT) in the device tree, and click Configuration.
   • In GHL Connect (Standalone): Go to the System page and click directly on Configuration.
   • In GHL Connect (EXT): Go to the System page, select Assign and configure connected PAB devices, and click the gear icon next to the respective PAB device.
3. Check the box “Doser 3 pump heads upgrade present” and save the change.

Cause

This issue is caused by a numbering conflict. By default, every GHL Doser is configured to “Start numbering” at index 1. When multiple units are connected via PAB, the system does not automatically renumber them. As a result, both the existing and new Doser may try to react to commands for “Pump 1-4”.

Solution

You must manually assign a unique starting index to each Doser in the PAB chain:

1. Open the Configuration:
   • In GHL Control Center: Go to the System page, highlight the Extension Doser in the device tree, and click Configuration.
   • In GHL Connect: Navigate to the System page, select Assign and configure connected PAB devices, and click the gear icon next to the Doser.
2. Set “Start numbering”: Change the value to the next available pump number and save the change.
   Example: If your Master Doser uses 4 pumps (1–4), set the first Extension Doser to Start numbering: 5.