HUMIDIFYING AIRHUMIDIFYING AIR

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Hello, I would like to talk to you about Hello, I would like to talk to you about humidifying air.humidifying air.

Relative humidity is one of the major Relative humidity is one of the major factors in achieving comfort conditions. It is factors in achieving comfort conditions. It is the amount, expressed as a percentage, of the amount, expressed as a percentage, of water vapour actually in the air compared water vapour actually in the air compared to the amount of water vapour the air could to the amount of water vapour the air could contain if it was saturated.contain if it was saturated.

Not all air conditioning systems are Not all air conditioning systems are equipped with humidifiers. In fact only a equipped with humidifiers. In fact only a few of the larger units or those designed few of the larger units or those designed for specific needs have humidifying for specific needs have humidifying capabilities.capabilities.

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

by a humidistat – a control which senses the value of by a humidistat – a control which senses the value of the relative humidity in the air and adds the moisture the relative humidity in the air and adds the moisture as required.as required.

This diagram shows the location of the water or steam This diagram shows the location of the water or steam sprays upstream from the cooling coil. By installing sprays upstream from the cooling coil. By installing the sprays in this location, surplus moisture can the sprays in this location, surplus moisture can removed by the finned cooling coil (if required). Also removed by the finned cooling coil (if required). Also the fins may catch any water drops to assist the the fins may catch any water drops to assist the evaporation of these drops into the air stream.evaporation of these drops into the air stream.

Humidifying is Humidifying is usually achieved by usually achieved by the use of fine water the use of fine water sprays or steam jets sprays or steam jets in the air stream. This in the air stream. This way the moisture is way the moisture is directly added to the directly added to the air and the operation air and the operation is controlledis controlled

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The water must vaporise in order for the relative The water must vaporise in order for the relative humidity to increase.humidity to increase.

Steam spray or injection are best applied when Steam spray or injection are best applied when the system is calling for heating rather than the system is calling for heating rather than cooling. The heat from the steam would assist the cooling. The heat from the steam would assist the heating process, whereas when cooling, the heat heating process, whereas when cooling, the heat from the steam would be working against the from the steam would be working against the cooling coil.cooling coil.

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