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TROUBLESHOOTING & REPAIR PROCEDURES
Model 400E Ozone Analyzer
Instruction Manual
252
P/N 04316 Rev: B
11.2.
Gas Flow Problems
In general, flow problems can be divided into three categories:
1.
Flow is too high
2.
Flow is greater than zero, but is too low, and/or unstable
3.
Flow is zero (no flow)
When troubleshooting flow problems, it is a good idea to first confirm that the
actual flow and not the analyzer’s flow detection hardware and software are in
error.
Use an independent flow meter to perform a Flow Check as described in
Section 9.3.5.
11.2.1.
Typical Flow Problems
11.2.1.1.
Flow is Zero
The unit displays a
SAMPLE FLOW
warning message on the Front Panel Display or
the
SAMPLE FLOW
Test Function reports a zero or very low flow rate.
Confirm that the sample pump is operating (turning). If not, use an AC Voltmeter to
make sure that power is being supplied to the pump. If AC power is being supplied
to the pump, but it is not turning, replace the pump.
If the pump is operating but the unit reports no gas flow, perform a Flow Check as
described in Section 9.3.5.
If no independent flow meter is available:
Disconnect the gas lines from both the Sample inlet and the Exhaust outlet on
the Rear Panel of the instrument.
Make sure that the unit is in basic SAMPLE Mode.
Place a finger over an Exhaust outlet on the rear panel of the instrument.
If gas is flowing through the analyzer, you will feel pulses of air being expelled
from the Exhaust outlet.