Hot weather has finally arrived this week, and it's left all of us sweltering and desperate to cool off.

And none more so than drivers, who have to contend with the sun shining in through glass windscreens, creating a baking greenhouse effect as they sit in dense traffic on a hot day, huffing in hot petrol fumes.

Given that it's not even advised to keep bottled water in your car during heatwaves, maintaining a cool temperature in the vehicle under direct sunlight can be especially challenging. That's why motorists are sharing a lesser-known tip about a button on the dashboard that can cool down your car more efficiently than air conditioning.

This button, marked with a small arrow and a symbol representing the interior of a car, is the 'recirculate air' button - an excellent method to cool down your car even when the aircon is off.

The reason being, it blocks all outside air and only recirculates the existing air within the car, as the name implies.

Interestingly, this feature also benefits hayfever sufferers as it prevents fresh pollen from entering through your vents.

The principle behind this is that the air outside your car is warmer than inside. Therefore, a quick blast of aircon will make the internal air much colder.

You can then continuously recirculate this existing air instead of replacing it with new warm air. This means you don't necessarily need to keep the aircon on as long as your windows are shut, saving fuel in the process.

A spokesperson for UK Car Discount explained the benefits of the handy feature in your car that could be a game-changer on those sweltering summer days: "Picture this: a blazing summer day and a parked car soaking up the sun's rays.

"The air recirculation button comes to the rescue, offering an effective solution to expedite the cooling process. By recirculating the cool air within the cabin, this button helps create a refreshing environment almost instantly.

"This becomes especially invaluable during scorching weather, allowing you to enter a chilled car free from the heat. No more waiting for the air conditioning to kick in the air recirculation button has your back, ensuring you experience a swift and soothing transition from the outside heat.

"It works by recirculating the cool air you get from your A/C when you first turn it on. The longer it's on for, the cooler your vehicle will get! If you don't use it, the car will use the air from the outside that is a lot warmer, and your A/C will work harder and continuously to cool the hot air."

The RAC backs this advice, adding: "Once the air conditioning is blowing cold, close all the windows and switch to (pre-cooled) recirculated air.

"You can now open the upper air vents and adjust the flow as required.

"More advanced ‘climate control’ air-conditioning systems allow you to set and maintain a constant temperature within the car."