Gasifier Not Ready Symptoms - Agilent Technologies 8860 User Manual

6 Maintenance and Troubleshooting

Gasifier Not Ready Symptoms

It is strongly recommended that the sample is pressurized to at least 1380 kPa above the vapor
NOTE
pressure of the mixtures at all times.
• Ensure GC functions normally (Refer to the "Low Peak Area or Height (Low Sensitivity)"
section of the GC User Manual.)
• Check if the vaporized flow coming out the transfer line is too low to provide representative
sample within flushing time period. If that's the case, increase the vaporized flow or increase
the flushing time. The typical flow range for 88XX series GC is 20~40 ml/min; for 990 micro
GC is 10~20ml/min (990 injector has rather large restriction, the flow out of gasifier should be
around 100 ml/min to get a 10~20 ml/min flow out of 990 micro GC)
• Check if the vaporizer temperature is set too low, increase the vaporizer temperature if needed
• Check for Gasifier leaks. (See
• If target analytes are chemically active, check if the connection parts between sample cylinder
and gasifier are not deactivated. The tubing in the gasifier undergo Agilent proprietary
deactivation treatment. When analyzing chemically active components such as H
sure the sample cylinder and the connections to the gasifier are deactivated.
Larger Peaks Than Expected
• Check that GC is configured with the right loop size and right column's dimensions
• Check the responses of components from low to high boiling points: if the areas of low boiling
point compounds and high boiling point compounds are out phased, it means fractionation
happens. It can be caused by:
• Low sample bomb pressure, samples are already partially vaporized in the cylinder. If this
It is strongly recommended that the sample is pressurized to at least 1380 kPa above the vapor
NOTE
pressure of the mixtures at all times.
• Samples are partially vaporized before entering the gasifier. Agilent Gasifier includes a
• Gasifier vaporizer temperature is too high. The gasifier has a very compact structure. If
• Carryover effect. (See
Gasifier Not Ready Symptoms
Gasifier Temperatures Never Becomes Ready
To be considered ready, a temperature must be at setpoint ±1 °C. If a temperature
never becomes ready, do the following:
• Check the electrical supply to Gasifier
Agilent 8860, 8890, and 990 Micro GC Gasifier User Manual
is the case, increase the sample cylinder pressure.
pressure reducing regulator and flow adjusting needle valve that are essential for flash
vaporizing. Please don't add unnecessary needle valve or restrictions not provided in the
installation kit between sample cylinder and the gasifier inlet. Such components lead to
pressure drop. The sample pressure drop may release a dissolved gas, thus causing the
liquid to bubble or foam. Remove those pressure reducing components.
the vaporizer temperature is too high, the heat may transfer to the sample inlet tubing.
Low boiling point components may undergo evaporation before entering vaporizer.
Decrease the gasifier vaporizer temperature.
"Contamination or carryover"
"Checking for Leaks" on page 53.)
on page 48.)
S, make
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