Managing Humidity Levels

Optimizing performance of a direct evaporative cooler and for best results in humid conditions

By design an evaporative cooler puts moisture into the air as part of the cooling process.  Modern evaporative coolers that use the Chillcel style of material have an increased ability to evaporate water as the air passes through the cooler compared to older coolers.  The increased level of evaporation produces a lower delivered air temperature and increased cooling effect.  

To optimize the performance of an evaporative cooler it is important to ensure adequate ventilation of air out of the house to prevent moisture build-up in the home, particularly on more humid days. 

Moisture builds up is due to a lack of airflow caused by either insufficient exhaust or fan speed selection. Whilst every house is different and people have different opinions on what works best for them, our recommendations to customers who believe they are experiencing moisture build up is:

·         If possible, select maximum fan speed – on days of high humidity the higher the better 

·         Due to the higher fan speed and airflow required for humid conditions you MUST increase exhaust openings to let moist air out – doors / windows open etc.

• Consider running on vent only at nighttime when overnight outside temperatures drop significantly whilst outside relative humidity increases. This can be especially useful if for security reasons doors and window opening are reduced at night.

Some simple rules of thumb useful when determining doors / window openings to prevent moisture build up -

• In every room with air conditioning vents, have an exhaust area of open window (or door) that is at least twice the size of the vent in that room. 
• The best approach is to open the windows or outside doors furthest away from the air conditioning vents or ducts.
• When running the unit at high fan speed, if you can’t leave a door 20mm slightly ajar without it slamming shut, or doors are difficult to open, then you need to increase the exhaust area.
• If running the unit at any speed, a piece of tissue paper should not be able to hold itself up to the fly screen. If it does, then you need to increase your exhaust area. 

EXTRACTS FROM OWNERS MANUAL BELOW: