Windsor-Essex remains under a heat advisory and air conditioners — and those who install them — can't keep up with the heat.
Several suppliers across the city have seen a dramatic increase in air conditioner sales as well.
"We seem to be experiencing a rise in air conditioner sales, as normal when we get these heat waves, and sales of dehumidifiers have been unusually high over previous years," said Steve Barrett of Canadian Tire
The Level 2 heat alert is in place through Friday.
Tim Lamanthia, who owns a heating and cooling business, installed four air conditioning units Wednesday.
"It just seems like when we take care of one or two customers, the phone's ringing and there's one or two more to do," Lamanthia said.
Temperatures are are expected to be 30 C or high, with a humidex above 40 C, the remainder of the week.
Lamanthia says some air conditioners simply can't keep up with the rising temperatures.
He says most air conditioners aren't designed to tackle temperatures as high as they have been this week..
"People will set it at, say, 74 F, so when it's 95 F outside . You're trying to make up a 20-degree temperature difference and that's pretty tough to do," he said.
Lamanthia's advice is to take care of your air-conditioning issues before the hot weather rush.
"Knowing the trend, on usually the third, fourth, fifth day into a heat wave like this, the phone will keep ringing until a cool front moves in," he said. "We've gotten double the calls for sure."