Evaporative air conditioners are a great alternative to traditional cooling methods. Fresh air from outside gets drawn in and cooled naturally, creating a healthy indoor environment that’s both eco and budget-friendly.
If you’re asking yourself how does evaporative cooling work, we’ll explain the ins and outs, some common misconceptions, and give you some practical tips to make smart decisions about cooling your home.
How Do Evaporative Air Conditioners Work?
The cooling sensation you feel when stepping out of a swimming pool on a hot day shows exactly how evaporative air conditioning works in your home.
The science of evaporation
Evaporative cooling uses a basic natural process. Water absorbs heat when it changes from liquid to vapour, so evaporative air conditioners take advantage of this process to remove heat from the surrounding air.
The relative humidity determines how well evaporative cooling works. Dry environments like Adelaide have air with little moisture, so water evaporates faster and creates better cooling. These coolers can lower air temperatures by over 15 degrees in the right conditions.
How fresh air is cooled and spread
Your roof-mounted unit pulls in warm outdoor air, which flows through special water-soaked pads. As the water evaporates from these pads, the air cools down before a fan moves the now cooled air through your home.
Traditional air conditioners have to recycle the same air, but evaporative systems constantly fill your home with fresh air. At the same time, the cooling pads filter out impurities to make the air cleaner.
Why open windows are essential
Unlike split system air conditioners, evaporative cooling systems need some windows or doors open. Since the system is constantly bringing in fresh air, the old air needs somewhere to go. Open windows or doors let the warm air escape, so you should partially open the windows farthest from the cooling unit to get the best results.
The system won’t work if you don’t ventilate properly. Warm, moist air gets trapped inside and stops the cooler from pulling enough fresh air through the cooling system.
Benefits of Evaporative Cooling Systems
Evaporative cooling brings more advantages than just cooling your space down. Adelaide homeowners choose these systems because they offer multiple benefits.
Lower energy consumption
Evaporative coolers use 50-75% less energy than traditional air conditioners since they don’t use energy-draining refrigeration cycles.
Less energy means lower bills and a better carbon footprint too – about 20% less than a standard refrigerated air conditioning system.
Healthier indoor air quality
The system’s biggest health benefit comes from supplying 100% fresh, filtered air without recirculation. Water-soaked cooling pads catch most airborne dust, pollen, and particles, which then wash down into the system’s sump. The air also gets a gentle moisture boost that helps prevent dry skin, sore throats, and irritated eyes.
Great for open-plan and outdoor living
Open-plan designs and larger living spaces are a great fit for evaporative coolers. The system works well with windows and doors slightly open, so you can have a cooler home without having to seal every exit and shut yourself in.
When Evaporative Cooling Works Best
You need the right conditions for evaporative cooling to work well. Some regions get great results, while others don’t see much benefit.
Ideal climate conditions
Two main factors determine how well evaporative cooling works: humidity levels and outdoor temperature. These systems work best when relative humidity stays below 30%. The cooling effect starts dropping as humidity climbs between 30-50%, with regular air conditioning becoming a better choice once humidity goes above 50%.
Why Adelaide is a perfect match
Adelaide has just the right climate for evaporative cooling systems. Our hot and dry summers create perfect conditions that let these systems run at their best. Most summer days in Adelaide have low enough humidity for evaporative systems to cool effectively, helping you beat the heat and save big on your power bills.
Limitations in humid environments
Humid conditions pose real challenges for evaporative cooling. The cooling power drops sharply once relative humidity passes 50%. High humidity means the air already holds lots of moisture, which leaves little room for more evaporation.
Evaporative Cooling Tips
Your evaporative cooling system will work better and last longer with proper installation and maintenance.
Choosing the right size and model
Your home’s airflow rate and total volume should determine your evaporative cooler’s size. The unit should be powerful enough to replace indoor air every 2 minutes for the best cooling results.
Importance of regular servicing
Ideally, you’d have a licensed technician service your system every 12 months, usually before summer gets into full swing. As evaporative cooling specialists, Air Conditioning Doctor can help your system last longer and perform better with regular maintenance.
A typical service check will clean filter pads, check water levels, inspect fan and motor parts, and verify proper water distribution. Your system can become less efficient and rack up higher bills without routine maintenance, so make sure you keep on a regular service schedule.
Water management systems
Modern systems manage water through:
- Dump cycles that swap out water after set times
- Quality management systems that replace water when needed
On a bleed system unit, the right bleed rate (11-20 litres per hour for standard systems) stops minerals from building up while saving water.
Smart controllers and automation
Smart features are available as an option in modern evaporative coolers. Wi-Fi controllers let you control your system from your phone, so your house is cool when you get home. Advanced systems also give you:
- Temperature and humidity tracking
- System programming to turn on and off automatically
Shut down over winter
Your system would benefit from a proper shutdown as winter approaches to prevent damage and extend its life. Here’s what you need to do:
- Switch off controller and isolator power
- Clean and drain the water tank
- Clean or put in new cooling pads
- Put a breathable cover on the unit
- Close ceiling vents to keep heat in
These steps protect your system from breeding algae, mould, and bacteria from growing during winter. It also helps to reduce corrosion and extends the life of the filter pads.
Keep your evaporative cooling system healthy with Air Conditioning Doctor!
As Adelaide’s evaporative cooling experts, our team at Air Conditioning Doctor can help you get the system right. We’ll give you the best advice for installation or changeover and keep your system running at its best with smart servicing and maintenance.
Call us today on 1300 723 413 to find out how you can stay cool while keeping your energy costs down during Adelaide’s hottest months.
Stephen Maitland is the Director of Air Conditioning Doctor and has over 20 years of experience in the refrigeration and air conditioning industry. He founded the company in 2007 to be Adelaide’s leading air conditioning repair, replacement and installation specialist.
As a certified Refrigeration Mechanic with a full unrestricted ARC license, his technical knowledge and years of experience allow him to diagnose problems quickly and offer practical and efficient solutions for his customers.
