Navigator 600 Phosphate
Multi-stream
Appendix C – Troubleshooting
IM/NAV6P/MS–EN Rev. F
71
Appendix C – Troubleshooting
C.1 Analyzer Malfunction
For the analyzer to function correctly and to specification, the
following conditions must be met:
The correct reagents and calibration solutions must be
connected.
The order that the reagents are introduced into the
reaction block must be correct.
The flowrate of all solutions must be correct.
The analyzer's electronics (transmitter and optical
measuring device) must be functioning correctly.
Virtually all problems with the analyzer are as a result of 1 or
more of these not being correct. For troubleshooting it is
important to remember the basic analyzer functionality with
respect to the 4 conditions above.
C.2 Single-Stream Mode for Maintenance
To carry out maintenance, switch to single-stream mode
(provided that a single stream is available) by disabling all
streams except one – see Section 5.4.1, page 31. If no streams
are available, introduce a solution via the secondary calibration
valve.
Single-stream mode stops multi-stream sequencing and
enables the display and the current output to respond quickly to
updates to color changes in the cuvette. This mode is used to
check the basic performance of the analyzer, such as response
or drift, without waiting for the normal stream update.
C.3 Calibration Errors and Noisy or Incorrect Readings
Symptom
Action
Failing calibration
(calibration
parameters
consistent from one
calibration to the
next)
Check the system for visible air bubbles – see Section C.3.1, page 72
Check that reagents enter the reaction block in the correct order – see Section C.3.3, page 74
Check reagents are correct – see Section C.3.3, page 74
Check solution flowrates – see Section C.3.3, page 74
Check operation of zero and secondary calibration valves – see Section C.3.4, page 74
Check mV values from the optical system – see Section C.3.2, page 73
Failing calibration
(calibration
parameters vary from
one calibration to the
next)
Perform a
Noisy readings
check – see below
Check operation of zero and secondary calibration valves – see Section C.3.4, page 74
Check mV values from the optical system – see Section C.3.2, page 73
Incorrect readings
(Calibrations pass
with consistent
results)
Check each stream reading independently. Switch off the sample flow to all streams except the one
being checked and remove the inlet tube from those constant head units, draining down the constant
head chamber. Measure each stream for at least 20 minutes or until stable readings are obtained. Ensure
the analyzer is configured for single stream operation – see Section C.2.
If readings are correct for individual streams but incorrect when the analyzer is running in multi-stream
mode, the problem is likely to be a leaking stream select valve. Replace the valve (see Appendix H,
page 83 – part number AW600034).
If all readings are the same as when run in full multistream mode:
1. Disconnect the cleaning solution tube from the clean valve manifold and check if the reading
changes after 30 minutes to 1 hour. If it does, the problem is likely to be a leaking clean valve.
Replace the valve (see Appendix H, page 83 – part number AW600034).
2. Disconnect the secondary calibration solution tube from the calibration valve manifold and check if
the reading changes after 30 minutes to 1 hour. If it does, the problem is likely to be a leaking
calibration valve. Replace the valve (see Appendix H, page 83 – part number AW600034).
If no problems can be found, it suggests that the laboratory method could be inaccurate.
Noisy / unstable
readings
Check the system for visible air bubbles – see Section C.3.1, page 72
Check mV values from the optical system for stability – see Section C.3.2, page 73
Check solution flowrates – see Section C.3.3, page 74
