Talks between Consolidated Edison Inc. (ED), the supplier of electricity to most of New York City, and its biggest union are “pretty grim” and there’s no sign of a resolution any time soon, a union official said.

“They sent a couple of crash-test dummies to the negotiating table who just sit there and nod their heads,” John Melia, a spokesman for Utility Workers Union of America Local 1-2, said in a phone interview today. Con Ed Chairman and Chief Executive Officer Kevin Burke “is playing a dangerous game that doesn’t make economic sense.”

More than 8,000 workers have been locked out by the company since July 1, after talks to extend their contract failed. Negotiations, which resumed yesterday with federal mediators, were “slow, but ongoing,” Sarah Banda, a spokeswoman for New York-based Con Ed, said in a phone interview. The company is using managers to fill in for the union workers.

The negotiations are taking place as New York City faces some of the hottest temperatures of the year. The city is forecast to reach 99 degrees Fahrenheit (37 Celsius) tomorrow, according to the National Weather Service.

“We’re always ready for anything coming our way, including hot weather,” Banda said.

Con Ed rose (ED) 5 cents to $62.14 at the close.

To contact the reporter on this story: Benjamin Haas in New York at bhaas7@bloomberg.net

To contact the editor responsible for this story: Tina Davis at tinadavis@bloomberg.net