Message: "ALERT Tube (X) weak. Tubing replacement recommended." What should I do?
IMPORTANT: This message can be falsely declared if your instrument has been idle for a period of time. To reduce the chance of false declarations always run a line charge or two at the beginning of a routine, especially after a period of idle time (e.g., after a weekend or a long holiday).
The ALERT message “Tube (X) weak. Tubing replacement recommended” is due to one or more of the pump tubes giving a low-pressure reading during the testing of the pump tubes at the start of the analysis. When the message is presented as an ALERT the problem can be ignored temporarily and addressed after the analysis is complete (Do not repeatedly ignore this message or you risk the pump tubes breaking and causing corrosion within the peristaltic pump). If the holding pressure of the pump tubes was very poor, you would see an E13 Pump Tube Failure message. This ALERT is cautioning you that the pump tubes are not holding pressure well. It is possible though that if the tubing is dry (e.g. if the instrument has been idle for a week) and if the lines have not been fully charged with the solutions the air in the lines can cause a weak tube message.
To diagnose the cause, follow these steps:
(1) Connect the Flush Tube Assembly (Part #: TDF70) to all of the supply ports with the middle connector attached to the water container.
(2) In the Diagnostics menu, run a Line Charge (ALL) several times to ensure the lines are filled with water.
(3) Run a Pump Tube Test, also found in Diagnostics.
This will display pressure results for each of the 6 pump tubes. The minimum to PASS is a reading of at or above 8 psi. If the results are between 5.0 – 7.9 psi you will see a WARNING. If the results are less than 5.0 psi the test will display FAIL. Running this test in Diagnostics will confirm the problem or show that it is corrected with proper charging of the lines.
(4) If the Pump Tube Test failed...
If the instrument fails the Pump Tube Test, generally the solution is to replace the pump tubes, but there can be other causes as described in TDF Service Procedure E13 Diagnosis. Depending on the software on your instrument, you would need either #TDF68 Silicone Pump Tubes (software version 3.60 or earlier) or #TDF99 Pump Tubes (software version 3.70 or later).
For more information on the weak tubes alert, see Service Procedure E13 Fault Diagnosis (TS001). For installation procedures, refer to TDF Service Procedure Silicone Pump Tube Replacement for TDF68 (TS003) and TDF Service Procedure Long-Life Pump Tube Replacement (TS028) for TDF99 to confirm the reason. If the instrument fails the Pump Tube Test, generally the solution is to replace the pump tubes, but there can be other causes as described in the Pump Tube Replacement Service Procedure.