The gas detector is used to detect the concentration of gas leak instrument. Gas detector can detect hydrogen sulfide, carbon monoxide, oxygen, sulfur dioxide, phosphine, ammonia, nitrogen dioxide, hydrogen cyanide, chlorine, chlorine dioxide, ozone and combustible gas and other gases, widely used in petrochemical, coal, metallurgy, chemical industry, municipal gas, environmental monitoring, and other places on-site detection. Measure to achieve special occasions needs; For tunnels, pipes, tanks, confined Spaces or gas concentration detecting leakage detection. Maintenance of the gas detector of do the following: 1, check the gas flow rate, usually for 30 / h, flow is too big or too small influence on the result of the analyzer. 2, change the filter paper: stop pump, filtering tank drainage. 3, check for leakage phenomenon in the pneumatic system. Sobs diaphragm pump with and without damage, sampling probe whether the seal is broken, and four-way valve and steam condensation for damage. 4, washing the sampling probe, sampling hole pipeline dredge. 5, check whether the condenser work normally, usually temperature adjustment in the range of 3 degrees Celsius. 6, check the meter to see if the dirt, cleaning in a timely manner.