Yes. During any winter months, low temperatures and reduced use allows moisture to stagnate in the water reservoir and filter pads, encouraging algae growth, bacteria and mineral deposits. Shutting the unit down blocks cold air from entering through air vents, protects components from frost and prevents costly repairs—keeping the evaporative system in top shape for next summer.

Does My Evaporative Cooler Need a Winter Shutdown?
Australia’s winter officially starts in just a couple of weeks, which means many of us will make the switch from cooling our homes to heating them as the cold weather takes hold.
The weather has remained unseasonably warm in recent weeks, though. It means that many of us have likely kept using our evaporative air conditioner systems to continue cooling our homes. But with the winter period getting ever closer, we may just start asking the question, “Does my evaporative cooler need a winter shutdown?”
Let’s take a look at how your evaporative system responds to shutting down for winter after a busy summer season, and how to go about it.
How Do Evaporative Air Coolers Work?
Evaporative air coolers are a cost-effective alternative to traditional air conditioners, especially in dry climates. They also boast a lower environmental impact than refrigerated air conditioning systems.
Also known as swamp coolers, they work by drawing in warm air and passing it through water-saturated filter pads. As the water evaporates, it absorbs the heat. It then creates cool air that the swamp cooler pushes into your home through ceiling vents.
Unlike refrigerant-based air conditioners, evaporative cooling increases indoor humidity without significantly increasing energy consumption. The system includes components like cooling pads, water reservoir and distributor channels to circulate moisture. Many modern evaporative air conditioners even have smart controllers that let you start the cooling process remotely.
Evaporative air conditioning offers benefits like comfort and lower energy bills. For optimal efficiency, though, it works best in low humidity.
When Should I Turn Off My Evaporative Cooler?
With the oncoming winter period increasing the coolness of the air inside your home, you may be wondering, “Does my evaporative cooler need a winter shutdown?” to which the answer is a resounding “yes”. The next will likely be “So when should I do it?”
Well, I’m glad you asked!
The best time is before winter sets in (i.e. now). Properly turning off your evaporative air conditioner does numerous things.
- It stops cold air entering the house.
- Reduces the risk of algae growth and bacteria buildup in the water reservoir.
- Improves the heating efficiency of your home heating solution.
During winter, standing water in the unit or pads can lead to costly repairs, mould growth and health risks as the air circulates through dirty vents. A winter shutdown of your swamp cooler protects its water supply, power supply and distributor channels. The cold weather can damage the unit if it’s not drained and isolated from the electrical supply.
Ideally, the optimal time to turn off the cooler is in March or April, just after the summer months and before the winter months start to take effect. The next best time is now.
What’s Involved in the Evaporative Air Conditioner Shutdown Process?
The good news? If you’ve only recently installed your evaporative cooling unit, and it is from a leading brand, chances are it has the ability to take care of its own shutdown.
There are several quality options available in Australia, like models from Braemar or Breezair, that require little input from the owner. These features are found in newer models, so if your swamp cooler dates back to a previous decade, the chances are a winter shutdown will be a manual job, one that can be physically demanding.
Thankfully, Metropolitan Air Conditioning is always available for the task of correctly shutting down evaporative air coolers. Contact us for a winter shutdown service, and our technicians will:
- Inspect the wear and condition of the unit
- Clean and flush the filter and cooling pads
- Drain and clean the water reservoir to stop vermin from entering
- Remove mineral deposits, dirt and grime before washing with soapy water
- Empty and clean the pump basket, filter and distributor channels
- Isolate the water supply line
- Isolate the electrical supply
- Secure the air conditioner with the supplied cover or tarpaulin
- Close off all air vents throughout the home
By using professional help from a licensed air conditioning technician, you can rest easy knowing your evaporative cooler is protected and ready for next summer.
The Associated Benefits of a Well-Maintained Evaporative Cooler
Maintaining your evaporative cooler year-round, including during the winter months, can offer several valuable advantages. Here’s why keeping your cooler in good shape is a smart move:
- Prolonged lifespan: Regular maintenance can make your evaporative cooler last longer. Cleaning and inspecting the system prevents avoidable wear and tear.
- Energy efficiency: A well-maintained cooler operates more efficiently, consuming less energy while delivering the same cooling performance.
- Improved air quality: Cleaned and well-maintained coolers are better able to remove dust, pollen and other contaminants and therefore can provide better indoor air quality.
- Consistent cooling capabilities: Regular maintenance helps your cooler maintain its cooling efficiency during the hot season.
- Cost savings: By preventing major breakdowns and costly repairs, maintenance saves you money in the long run. Small issues can be addressed before they turn into expensive problems.
- Winter preparedness: Properly shutting down your evaporative cooler for the winter is essential. Maintenance ensures it’s ready to hibernate without damage. Plus, you won’t encounter unpleasant surprises when you need it again in the spring.
So, whether it’s summer or winter, taking care of your cooler is a wise investment in home comfort and your wallet.
DIY Air Conditioner Winter Shutdown
At this point, we’ve answered the question “Does my evaporative cooler need a winter shutdown?” and determined that answer to be yes.
The next question you might have is, “Can I do it myself?” And the answer to that is yes, as long as the process doesn’t move into regulated plumbing or electrical work. Anything beyond routine maintenance tasks will, by law, require a licensed technician.
The first step to shutting down your evaporative air conditioner is to disconnect the power to the unit if it’s safe to do so and shut off the tap that supplies the water. Next, drain the reservoir and clean it with soapy water to get rid of the dirt and grime. Then give the filter pads a good clean.
Also, make sure the vents are closed. Leaving them open can be a real chink in your insulation. Finally, it’s time to deploy the cover. By covering the unit in winter, you protect it from potentially freezing conditions and limit the risk of insects and other pests setting up shop.
If you safely follow these steps, your evaporative air conditioner will be nicely primed and ready for another summer of cooling. Just be mindful of the risks and always follow the appropriate safety precautions. If ever in doubt or you determine that the process requires more than basic maintenance tasks (i.e. regulated plumbing or electrical work), contact a professional ASAP.
Metropolitan Ready to Shut Down Your Evaporative Cooling for the Winter
For peace of mind, contact Metropolitan Air Conditioning before the weather drops, and we’ll put your evaporative cooler into hibernation. We work with Australian-designed systems that best suit our dynamic climate conditions.
Please note: Thanks for reading our blog “Does My Evaporative Cooler Need a Winter Shutdown?” This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.
Frequently Asked Questions
If "Does my evaporative cooler need a winter shutdown?" is the question, then we've got the answers!
First turn off the power and water supply to the unit. Drain the reservoir, then wash it and the cooling pads with warm soapy water to remove dirt and mineral deposits. Rinse the filter pads, clear the distributor channels and let everything dry. Any work beyond these routine tasks—like dealing with fixed electrical supply lines—should be left to a licensed tech.
A winter shutdown closes air vents and any automatic winter flap, stops cold air from coming back into living spaces. With the evaporative cooler sealed, your heater warms the air inside faster and uses less power. Eliminating drafts means the home holds its temperature longer, uses less energy than running the heater while the cooler is open to the cold outside.
Standing water in an idle evaporative air cooler stagnates, allows bacteria, mould and algae to grow. As temperatures drop, that water can freeze, expand and crack the reservoir or distributor channels. When you turn the unit back on next summer, contaminated water and damaged parts will reduce cooling and create health risks—often leading to expensive repairs that a proper winter shutdown would have prevented.
Published: 2025-05-14