Low thermostat settings in the office is driving up the sales of space heaters even during summer. According to Tom Flippo, manager at Bering's on Bissonnet, while the bulk of their heaters are sold during winter, an average of 100 space heaters are purchased during the hot months.

Most of the buyers are office workers who find the thermostat setting too low for comfort. According to Don Young, vice president of the International Facility Management Association, the top two complaints of office workers in various countries were the office was too cold or too hot.

Offices in large buildings often prohibit space heaters for being fire hazards and energy inefficient.

The price of space heaters ranges from as low as $15 up to $300, which comes with an air filter. The models in the market offer units that run on natural gas, propane or electricity.

Young said in newer buildings, space heaters are no longer necessary because it has flexible temperature control systems. But for older buildings, other manual methods of coping with the extreme cold air could be used such as moving a chilly worker to a sunny window or just away from the aircon vent.