The stifling temperatures were clearly also bringing an onslaught of the creepy crawlies, with insect spray sales up more than 20 per cent on last year.
Ant repellent sales were almost double that of last year and bug repellents were also up more than 23 per cent.
When it came to food, sales data showed fresh was apparently the best to conquer the heat.
Countdown had already sold more than 108 tonnes of coleslaw so far this summer - the equivalent to the weight of 54 caravans.
Kiwis were also buying plenty more watermelons and nectarines than usual.
Countdown's merchandise manager Scott Davidson said the data suggested Kiwis were ejoying entertaining and barbecues as the hot weather continued.
"It's well known that last year we didn't have a very hot summer, so this year we are making the most of the hot nights and entertaining as much as possible," he said.
Davidson said there had also been record numbers of online shopping deliveries across the country, as Kiwis opted to head to the beach rather than the shops.
Countdown's top sellers this summer:
• New Zealanders bought more than 640 tonnes of ice, which is enough to fill more than 20,000 chilly bins.
• Water sales up more than 18 per cent.
• Fans have almost sold out across the country and sales have increased by double digits on last year.
• Insect sprays are up more than 20 per cent.
• Ant repellent sales are almost double last year and since the beginning of summer we've sold more than 15,000 packs.
• Bug repellents are up more than 23 per cent as this summer's extreme heat has meant there are more bugs, mozzies and ants around the house.
• Ice cream sales have increased more than 20 per cent.
• Kiwis are also choosing healthy snacks to get relief from the heat with watermelon sales significantly higher than last year and nectarines increased more than 20 per cent.
• Bagged salads has increased more than 15 per cent this summer.
• This summer, Countdown has already sold more than 108 tonnes of coleslaw, the equivalent to the weight of 54 caravans.