How to use your car air conditioner in summer

Those who have an older or less-equipped vehicle with no air-conditioning are in for a rude awakening. What an indispensable tool in hot summer weather!

The key is to use it properly, not only to cool the cabin efficiently but also to avoid wasting fuel and the resulting pollutant emissions. According to Natural Resources Canada, turning on the air conditioning while driving can increase fuel consumption by 20%. The percentage varies according to a multitude of factors: cabin volume, outside temperature, required inside temperature, vehicle insulation, etc.

And that's without mentioning the breakdowns and defects that can result from overuse, necessitating a costly visit to the garage. Hot just thinking about it? Don't worry, we've got a few tips to help you get the most out of your car air conditioner:

1. Keep cool on the move

An air conditioner works much better when you're driving. The faster the engine is running, the more the air-conditioning compressor is activated and the cooler the interior of the car becomes. There's little point in leaving it on for a few minutes before setting off.

If the cabin is really hot, increase the fan speed and roll down the rear windows for about 20 seconds, which will get all the hot air out quickly. Leave the front windows up, however.

2. As cold as possible

Setting the air conditioner to the lowest possible temperature and adjusting the fan increases efficiency, dries the air less and saves fuel. And why? By setting the temperature lower, the air conditioner will have to warm up some of the air, which requires more effort and therefore more fuel. If you have a "Max A/C" function, use it.

3. Recirculating the air... yes and no

When the air leaving the air conditioner becomes cool, close the windows and press the air recirculation button. This will prevent the warmer outside air from spoiling your efforts. However, if you have rear passengers, turn off the air recirculation mode. This takes air from the front seats and feeds it back into the system, so while you may be cool behind the wheel, those on the bench may be enduring warmer air.

4. A stop/restart system, no thanks

If your vehicle has an engine stop/start system, turn it off. Yes, it saves a small amount of fuel, but the air-conditioning compressor stops working at the same time. In very hot weather, the interruption of cold air is felt quite quickly, making waiting at red lights even more unpleasant!

5. A clean filter

When you get the chance, inspect the cabin air filter. If it's dirty and clogged, air circulation will be affected. You should consider replacing it. In most recent vehicles, this filter is accessible behind the glove compartment, so there's no need to call in a technician.

Finally, remember to park out of the sun whenever possible, and to close the sunshade on the sunroof on hot days. You can also leave the windows slightly ajar and cover dark leather seats with light-colored sheets. And don't forget to have your air conditioner checked and serviced immediately if you notice that it's running less efficiently.