Evaporative Systems (Cooling Only)

Generally seen as an older technology, however with today’s advances on inverter motors they can be a great cost-effective system when it comes to general power consumption when running.

As the name suggests, an evaporative air conditioner uses evaporation to help cool the air. Based on the principles of evaporation, hot and dry outside air, is pumped through water-soaked cooling pads. As the air is pushed through the cooling pads, the water evaporates and the heat in the air is absorbed, which lowers the air temperature. A fan then pushes the cool air throughout a house via a network of ducts which will send air through into different areas of the house.

Some of the benefits of an evaporative air conditioner are;

  • Low running costs with Modern and innovative evaporative cooling can save you up to 80% on energy bills compared to a reverse cycle air conditioner
  • Evaporative air conditioners use a small amount of water, in many instances using almost 83% less water over the summer months than a shower
  • Fresh air is a major benefit of evaporative air conditioning, supplying 100% fresh, cool, outside air, all while delivering superior energy efficiency compared to a refrigerated equivalent.
  • Being a water cooled system ensures that the unit is environmentally friendly.

Some disadvantages of an evaporative air conditioner are;

  • Due to being water cooled, temperature control is limited
  • The system does not perform well on humid/muggy days
  • Can cause issues with asthma or respiratory issues if not serviced and cleaned professionally on a regular bi annual basis.


Evaporative AC FAQS

Can I control the amount of cooling in different areas of the building?

Yes, if you close a window in a room and open the internal door, the cool air will move into other areas, where there is an external opening. We recommend that you experiment so you can get the best out of your air conditioner – but remember that there has to be an exhaust opening to the outside of the house for the cooling to work properly.

Do I have to leave my doors and windows open?

No, an alternative to opening a window or outside door is to install security vents, or relief ducts, that exhaust the air from the building, we supply and install these also.

Will the evaporative cooler increase humidity and produce condensation in the building?

No, the evaporative air cooler will not increase the humidity – provided that the design is based on a balanced ventilation scheme. Keeping doors and windows open, or using an exhaust fan will let any humid air out, avoiding condensation.

Why does my evaporative air conditioner drain some water every now and then?

This is normal if a water management or ‘Watermiser’ drain system is fitted. These drain systems are designed to monitor and control the quality of the water in the tank. So, it only drains water when the system really needs to. It does this by letting water out through the drain, which is replaced with fresh water via water inlet float valve as the water level in the unit drops. If you have an older style evaporative system, they are generally fitted with a bleed off drain that constantly drips a small amount of water when running in order to let fresh water up into the system.

How energy efficient are they?

As per Canstar Blue 2020 study;

Ducted evaporative coolers are the energy-efficient alternative to regular air- conditioning, but just how much do they cost to run?

In this table we assume a 5-10kw system uses 413 watts an hour, a 10-15kwh system 734 watts, and a 15-20kw system 1,064 watts an hour. For a small unit, 5-10kw system may suffice, but a medium sized house is more likely to need 10-20kw.

How they Look?




Evaporative Brands We Work With

Evaporative SystemReverse Cycle Wall Mounted Split Systems


If there are outlets throughout the house in the ceiling, you know it’s Evaporative. If it’s on the wall it…
Evaporative SystemGas HeatingReverse Cycle System


Use our identification help guide to see what Braemar system is installed. In most cases in Perth, if there is…
Evaporative System


Cooling only system.
Evaporative SystemReverse Cycle Wall Mounted Split Systems


The majority of systems in Perth are Evaporative units, however there are still some gas heater systems we see. Use…
Evaporative System


Cooling only system.
Evaporative System


Cooling only system.
Evaporative System


Cooling only system.
Evaporative System


Cooling only system. Very old evaporative systems.