Evaporative coolers cool and filter the air. Hot outside air is drawn through a water-moistened filter and then blown through the house. To work effectively, windows and/or doors must be left open so this moist air can be exhausted from the house.
Evaporative coolers are generally more suitable for areas where humidity is low. If the outside air is already humid then the cooling effect of the unit is limited.
Low running costs
Medium purchase cost
Cool air but increase humidity
Portable or fixed
Must have windows or doors open
Types of Evaporative Coolers
Suitable for small rooms (up to 25m2)
Require standard power outlet
Best positioned near an open window or external door with an opening on opposite side of the room
Look for models with water level gauge, variable fan speed and directional louvres
Fixed Room Units
Suitable for open areas 30-50 m2
Location – external wall/window
Permanently wired and plumbed
Install towards prevailing summer winds (see considerations)
Ducted Whole House (Central Systems)
Suitable for whole home cooing
Cool air is ducted into rooms through ceiling outlets
Existing heating ductwork is usually not suitable
Careful consideration in water restricted areas
Site the unit on the side of the house which receives the prevailing hot winds. This avoids too much heat leaking in from the open windows and doors that exhaust the air.
On high humidity days the highest fan speed should be used. If it is a very humid day, turn off the water supply to the cooler and run the fan only.
Water consumption for evaporative coolers depends on the natural humidity of the day.
Evaporative coolers do not work on a thermostat. They run for as long as you leave them on.
During winter, ducted units on the rood should have covers placed over them and ceiling vents closed to stop excessive heat loss.