CHICAGO (CBS) – ComEd and Chicago firefighters were kept busy on a sweltering Friday as utility power equipment sparked or caught fire across the city.

The first one occurred near the CTA’s Blue Line at Milwaukee and Damen. That knocked out power to a wide area of Wicker Park.

Resident Bill Bean saw the blowout from his window.

“I heard a whole bunch of popping, like 15 or 20 times,” he told CBS 2’s Mike Parker.

Soon after, CBS 2’s Kris Habermehl in Chopper 2 was over the Hubbard and Grand area, watching another piece of electrical equipment blow up in the heat. It sparked for a time, and then the power pole went up in flames.

Power went out in the West Loop area, too, but the Aberdine Tap kept running – to the delight of some overheated patrons.

“No power, no food, cold beer – cash only,” employee Nika Thiel said.

CBS 2 learned of at least six fires that may have been transformers going up in flames. ComEd could not provide a breakdown of all the damage but said some customers lost power.

Also Friday, several firefighters had to be treated for heat exhaustion while trying to put out a fire on the North Side.

The fire started on a back porch of a 3-story building near Southport and Belmont. The flames quickly spread to porches on several floors.

More than 100 firefighters were called in so that firefighters could rotate in the hot weather. Still, 10 of them were checked for heat exhaustion.

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