AS 100 autosampler takes up more sample than expected

Applies to

ALEXYS system, AS 100 autosampler

Summary

AS 100 autosampler takes up more sample than expected.

Cause

Depending on the injection method, the sample consumption can be calculated. The (needle) flush volume must be added to the sample volume. Abnormal sample consumption can be caused by:

1. a combination of leakage in the sampling tubing or valve in combination with headspace pressure. During injection air pressure is applied to sample vial and sample disappears through a leak
2. headspace pressure is used without a cap on the vial (or a leak in cap) and sample sputters out of the vial
3. another cause

Diagnosis and Remedy

Check for leakage and repair. Turn off the headspace pressure.