HUMIDIFYING AIR © Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence

 Hello, I would like to talk to you about humidifying air.  Relative humidity is one of the major factors in achieving comfort conditions. It is the amount, expressed as a percentage, of water vapour actually in the air compared to the amount of water vapour the air could contain if it was saturated.  Not all air conditioning systems are equipped with humidifiers. In fact only a few of the larger units or those designed for specific needs have humidifying capabilities. © Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence

by a humidistat – a control which senses the value of the relative humidity in the air and adds the moisture as required.  This diagram shows the location of the water or steam sprays upstream from the cooling coil. By installing the sprays in this location, surplus moisture can removed by the finned cooling coil (if required). Also the fins may catch any water drops to assist the evaporation of these drops into the air stream. Humidifying is usually achieved by the use of fine water sprays or steam jets in the air stream. This way the moisture is directly added to the air and the operation is controlled  Humidifying is usually achieved by the use of fine water sprays or steam jets in the air stream. This way the moisture is directly added to the air and the operation is controlled © Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence

 The water must vaporise in order for the relative humidity to increase.  Steam spray or injection are best applied when the system is calling for heating rather than cooling. The heat from the steam would assist the heating process, whereas when cooling, the heat from the steam would be working against the cooling coil. © Commonwealth of Australia 2010 | Licensed under AEShareNet Share and Return licence