It is vital to remove moisture from compressed air systems; otherwise, water will condense out causing blockages in pipelines and in equipment. This is particularly important for instrument air.
Compressed air used to operate process instruments should be dried to a dew point of between -20ºC and - 40ºC. Process air can be supplied at higher moisture contents.
Typically it should be dried to a dew point of about 0ºC. This should be sufficient to prevent condensate collecting in the distribution pipe work, except in very cold climates, where lower moisture levels may be needed.