Air Cooler vs Air Conditioner: What’s the Difference & Which to Buy?
The UK’s weather is changing for real: hotter summers, more frequent heatwaves, and plenty of days hitting 30°C or more. If you’re fed up with tossing and turning through sweaty nights or struggling to focus in a sweltering home office, you’re probably thinking about how to keep cool.
But when it comes to cooling off, choosing between an air cooler vs air conditioner isn’t always straightforward. They might sound similar, but they’re built for different needs. In this guide, we’ll break down how each one works, what sets them apart, and which makes more sense for your space, budget, and lifestyle.
What Is an Air Cooler?
An air cooler, also known as an evaporative cooler, works by drawing in warm air and passing it over water-soaked pads. As the water evaporates, it cools the air, which is then blown into the room.
This type of cooling adds moisture to the air, so it works best in dry or well-ventilated spaces. You’ll typically need a window or door open nearby. Because they use only a fan and a small water pump, air coolers are energy-efficient and inexpensive to run.
What Is an Air Conditioner?
An air conditioner, or AC for short, removes heat instead of creating “cold” by circulating a refrigerant through a four-part loop—compressor, condenser, expansion device and evaporator—that continuously absorbs indoor heat and releases it outdoors.
In most systems, the compressor and condenser sit in an outdoor unit, while the evaporator and fan are indoors. Refrigerant lines connect the two, allowing the system to cool and de-humidify recirculated indoor air behind closed windows.
Because of this process, air conditioners offer powerful, consistent cooling and precise temperature control. However, this performance also means higher upfront costs, more electricity use, and usually professional installation.
Modern split AC systems have improved on these downsides by using inverter compressors for better energy efficiency and low-GWP refrigerants that are less harmful to the environment.
There are also single-unit portable air conditioners, which use the same cooling process but combine all parts into one machine. Instead of an external condenser, they use an exhaust hose to vent hot air outside through a window or door.
Air Conditioner vs. Cooler: Core Differences
As you can see, both air coolers and air conditioners help cool your space, but they work in very different ways. And that means different costs, benefits, and ideal use cases. Here’s a detailed comparison of air conditioner vs cooler:
How they work
Air coolers pull warm air across wet pads; the water evaporates, lowering the air temperature before a fan pushes it back into the room. No chemicals, just fan power and a small water pump.
Air conditioners circulate a refrigerant in a closed loop; a compressor drives heat from indoor coils to an outdoor condenser, expelling it outside and sending chilled, de-humidified air back in.
Cooling power & humidity
Air coolers typically drop temperatures by about 5–10°C in low-humidity climates and add moisture as they cool.
Air conditioners can achieve far larger temperature drops and actively remove humidity, so rooms feel cooler even in muggy weather.
Ventilation vs. sealed rooms
A cooler needs an open window or door so warm, moist air can escape; without that cross-flow, it quickly loses effectiveness.
An air-conditioner works best in a closed room where it can recirculate and steadily lower both heat and moisture.
Energy use & running costs
Tests show air coolers can use up to 75% less electricity than comparable portable AC units.
A typical 1 kW portable air-conditioner draws about 1–1.3 kWh of electricity and costs roughly £0.27 per hour at current UK tariffs.
Installation & upkeep
Air coolers are super easy to set up. All you need to do is fill the water tank, plug it in, and you’re good to go. They’re also lightweight and often come with wheels, so you can move them around your home without any hassle. Maintenance is just as simple: just clean the water tank and pads now and then.
While many portable AC units are easy to install on your own, split systems require professional installation, periodic servicing, and safe handling of refrigerants.
Noise & comfort
Consumer tests put many evaporative coolers around 50 dB, the level of a quiet conversation.
AC units, especially portable ones, can be louder due to the compressor, although premium inverter models can be quieter.
Environmental impact
Air coolers don’t use refrigerants and have a lower carbon footprint.
Older ACs may contain HFCs (hydrofluorocarbons), whose global-warming potential is hundreds of times that of CO₂, though newer gases and tighter leak rules are cutting that footprint.
Quick comparison: air conditioner vs air cooler
Feature | Air Conditioner | Air Cooler |
How it works | Uses refrigeration to remove heat | Evaporates water to cool incoming air |
Best for | Sealed rooms, humid or very hot conditions | Dry, well-ventilated spaces |
Humidity impact | Reduces moisture | Adds moisture |
Cooling strength | Strong, consistent cooling | Light, gradual cooling |
Energy usage | Higher | Low |
Running cost | More expensive to run | Budget-friendly |
Noise level | Can be louder (especially portable units) | Quiet (like a fan) |
Installation | Often requires installation | Plug-and-play |
Environmental impact | Depends on refrigerant type and efficiency | Low (no refrigerants) |
Air Conditioning or Air Cooler: Which One Should You Choose?
So, should you choose an air cooler or AC unit? It depends on your space, needs, and preferences:
Go for an air cooler if...
You live in a dry or well-ventilated space where you can keep a window open.
You want a simple, low-cost way to cool a room on warm—but not scorching—days.
You’re looking for something energy-efficient and environmentally friendly.
You don’t mind a bit of added humidity.
You want something you can easily move and set up without installation.
Choose an air conditioner if...
You need powerful, reliable cooling during heatwaves or in muggy weather.
You’re cooling a larger or well-insulated room where fans and coolers don’t do enough.
You want precise temperature control and the ability to remove humidity.
You’re okay with higher running costs in exchange for stronger performance.
You’re prepared for a bit more setup—whether it’s a portable unit with a vent hose or a fixed installation.
For those who want the cooling power of an air conditioner without permanent installation, the EcoFlow WAVE 3 Portable Air Conditioner offers a smart, flexible alternative. It’s a portable unit with serious performance—delivering 6,100 BTU of cooling and 6,800 BTU of heating in a compact, travel-friendly form. Whether you’re dealing with a heatwave at home or staying cool in a tent, van, or off-grid setup, the WAVE 3 can drop the air by 8°C in as fast as 15 minutes.
One of its standout features is the optional 1,024 Wh battery, which gives you up to 8 hours of cordless runtime in Eco mode. You can recharge it in as little as 75 minutes using a mix of AC and solar, or even charge it on the go from a vehicle. That kind of flexibility makes it ideal for campers, renters, and anyone who wants reliable cooling without drilling holes or committing to fixed units.
It also includes smart controls via Wi-Fi and Bluetooth, with multiple modes like Auto, Sleep (running as quietly as 44 dB), and Pet-Care, which adjusts temperature automatically throughout the day. It’s built with an IPX4 rating for weather resistance and uses R290 refrigerant, which is more climate-friendly than traditional gases.
EcoFlow WAVE 3 Portable Air Conditioner
Conclusion
Deciding between an air cooler vs air conditioner really depends on what matters most to you. If you’re looking for a budget-friendly option that’s easy to maintain and works well in smaller, airy rooms, an air cooler might be the way to go.
But if you want strong, consistent cooling—especially for larger or insulated spaces—an air conditioner is definitely worth the extra investment. Take a moment to think about your space and how you’ll use it, and you’ll be in a good spot to choose the cooling option that keeps you comfortable without spending more than you need to.
FAQs
Which is better air cooler or air conditioner?
Choosing between an air cooler and an air conditioner depends on your climate, budget, and needs. Air coolers are budget‑friendly, eco‑conscious, and use up to 75% less electricity. They work best in hot, dry climates with good ventilation.
Air conditioners deliver more powerful, consistent cooling (even in humid conditions), with the ability to set precise temperatures, but they’re more expensive to buy, run, and maintain. In the UK’s mixed climate, a cooler may be ideal for drier spells, but for guaranteed comfort during humid heatwaves, an AC is a more reliable choice.
What are the disadvantages of an air cooler?
Air coolers have several downsides. Their cooling capacity is limited, typically only reducing temperatures by around 5°C, so they won’t match an AC’s chill. They’re also ineffective in humid weather, adding moisture and making rooms feel clammy. You’ll need to refill the water tank daily and clean it regularly to avoid mold or bacteria buildup. Plus, they require good airflow. If placed in a closed room, their effectiveness drops and humidity rises.
Can an air cooler cool a room?
Yes, with the right conditions. A good model can lower the temperature in a room of 15–30 m² by a few degrees, especially in dry, well‑ventilated spaces. They work on evaporation: warm air passes through water-soaked pads and blows out cooler, moistened air. While you won’t reach the low temps of an AC, you will feel noticeably cooler and more comfortable as long as windows or doors allow airflow in and out.
Does air cooler work like AC?
No, an air cooler and an AC operate differently. An AC uses a refrigerant compression cycle (and dehumidifies air) to chill the entire room to a set temperature, regardless of humidity.
By contrast, an air cooler relies on evaporative cooling—passing air through damp pads and adding moisture. This makes the air feel cooler, but it offers less powerful temperature control and cannot dehumidify—meaning the effect is limited in high humidity.