Posted by on Monday, December 19, 2011 Under: Air Handling
One of the main problems for many swimming pools is condensation. Condensation happens when the water vapour in the air condenses into liquid water and forms a film on surfaces. This will then start to attack the fabric of the building and lead to expensive repair bills further down the road. For the pool operator, the objective is to keep this condensation to a minimum. This can be achieved by being aware of the temperature at which the water vapour in the air will condense into liquid water (otherwise known as the Dew Point). If you have a dew point of, say 24 degrees celsius, this means that if the water vapour in the air stays above that temperature, it will remain as water vapour. As soon as it drops below that temperature (for example, when it penetrates into the porous concrete walls of a building) the water vapour will become liquid water (ie, condensation). Therefore a high dew point is not good.

The two things that affect the dew point are: temperature and relative humidity. The relative humidity refers to the amount of water vapour in the air, expressed as a percentage of the maximum possible amount of water vapour there could possibly be in the air at that time. A relative humidity of 100% means that the air is holding the maximum amount of water vapour that it possibly could and is therefore said to have reached saturation. Warm air is capable of holding more water vapour than cool air.

Click here for an interactive tool that allows you to see how temperature and relative humidity affects the dew point.

In : Air Handling 

Tags: "condensation" "dew point" "water vapour" "saturation" "air temperature"