Education Hub

When is the ideal time to turn on your air conditioner?

Smartphone image with Air conditioner controls

Summer is approaching and coming along with it are uncomfortably hot temperatures. We’re often teased with a sprinkle of summer in April and May, and for some, that is reason enough to put on their shorts and crank the air conditioning.

We’re all about conserving energy, saving money and living comfortably here at A1. Because of this, we have set out on a quest to find the ideal time to turn on your air conditioner.

We will use the World Health Organizations (WHO) standards for a healthy indoor temperature to find out. The WHO recommends 18⁰ Celsius as a minimum for indoor temperature but recommends 21 degrees if there are any children or elderly people in the home. Overall the range of temperatures they deem safe is 18⁰to 22⁰, but we’ll stick with the 21⁰.

According to, the temperature in Toronto only reached above a high of 20⁰ twice in April and nine times in May.

Although temperatures fluctuate a great deal throughout April, May and even June, the average high temperature doesn’t rise above 21⁰until early June. However, the average low temperature doesn’t reach above 18⁰ until the end of June.

Woman holding and playing with child in living room cooling

While there are different preferences for temperature and certainly fluctuations in temperature on specific dates from year to year, it’s likely that you won’t need to turn your air conditioning until early June at the earliest.

The low temperature reaching a comfortable level much later than the high also stresses the importance of a programmable thermostat. Your temperature needs will change drastically depending on the time of day, so ensuring that you conserve energy while the outdoors will cool your home for you is essential to lowering energy costs.

Taking this data into consideration, we have decided to officially name June 1st Southern Ontario’s “Turn on your Air Conditioner Day”. We recommend you hold out on starting your home cooling system until then to reap the rewards of lower energy costs.

To reach the utmost level of efficiency, however, you should be making sure your air conditioner is ready for our official launch into the cooling season.

Schedule a Check & Clean for your system today!


Subscribe me to the A1 e-newsletter to receive tips & special offers

© 2022 A1 Air Conditioning & Heating, All Rights Reserved.