low nitrogen purity in nitrogen generators fall into four categories

low nitrogen purity in nitrogen generators fall into four categories: gas source quality, carbon molecular sieve condition, operating pressure, and valve malfunction .

• Compressed air containing excessive amounts of oil, water, or impurities can contaminate the carbon molecular sieve, leading to a decrease in its adsorption capacity.
• If the front-end filter cartridge is clogged or has not been replaced after its expiration date, its filtration effect will fail, and oil will directly enter the adsorption tower.
• The dehumidification effect of the refrigerated air dryer decreases, and the moisture content of the compressed air increases abnormally when the ambient temperature rises in summer.

• Carbon molecular sieves become ineffective due to aging, pulverization, or poisoning; their adsorption capacity naturally declines over time, and their lifespan is typically 5-10 years.
• Internal leakage in the programmable valve, coupled with worn seals, allowed high-oxygen-content gas to seep into the product gas from the regeneration tower, directly lowering its purity.
• Insufficient pressure can result from aging pipe joints or faulty pneumatic valve seals causing hidden leaks.

• Adsorption pressure that is too high (above 0.8 MPa) or too low (below 0.6 MPa) disrupts the normal adsorption-desorption equilibrium.
• The actual gas consumption exceeded the nitrogen generator's rated output, and the molecular sieve couldn't complete adsorption before switching off.
• The adsorption/regeneration switching time parameter setting is incorrect, or the oxygen probe of the nitrogen analyzer is aging and inaccurate.

Troubleshooting is recommended to follow the order of "instrumentation first, then air source, and finally adsorption." In most cases, improving front-end air purification, stabilizing adsorption pressure, and regularly replacing filter cartridges can resolve more than 80% of purity issues.