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Generally speaking, a gas chromatograph is divided into five parts: the gas path system (gas cylinders and gas pipelines), the injection system (vaporization chamber), the separation system (chromatography column), the detection system (detector), and the recording system (which now generally refers to a workstation). The most crucial one among them is the separation system, which is the core of chromatographic analysis. If there is a problem with the chromatograph, the causes are generally sought in the following five areas: 1. Gas supply system: A. Leaks: These are usually caused by inadequate tightening or worn-out gaskets; soap water can be used to check for leaks. B. Blockage: This is usually caused by impure gases; it can only be diagnosed through sectional inspection. In the case of capillaries, it is sometimes due to graphite shavings blocking the capillary tube. C. Impure gas: First, the purity of the gas purchased does not meet the requirements; second, there are no purification tubes installed in the gas pipeline. 2. Injection system: A. Clogging: Usually caused by carbon deposition resulting from excessive sample analysis in the vaporization tube; it should be removed and cleaned. B. Silicone rubber leakage (can also be included in the gas circuit system): Replace the silicone rubber. 3. Separation system: The main issue is the improper selection of the chromatography column; however, in most cases, the analysis methods are provided by others ； The service life of a chromatography column can only be determined by someone with practical experience. 4. Detection system: A. Numerous spurious peaks: This is usually caused by contamination of the detector; clean the detector (this issue can also arise due to impure inlet gas). B. No peak shape: no bridging current in heat conduction, or the hydrogen flame is not ignited due to water or air leakage. 5. Recording system: Nowadays, they are mostly workstations; it’s sufficient to be familiar with the standard operating procedures for such workstations. If that doesn’t work, reinstall the workstation. In short, when a malfunction occurs, as long as you follow the steps mentioned above, resolving common issues should not be a problem. It is also very necessary to be familiar with the manuals for all instruments