Along New York City’s steamy sidewalks in the summer, there’s long been a reliable respite from the heat: waves of air-conditioned comfort wafting from open doors.

Now the nation’s biggest city is pushing businesses to cool it on such wastefulness. Under an expanded law that took full effect this week, most stores and restaurants could be fined $250 or more if they keep their doors or windows open while running the A/C.

But as temperatures soared into the 90s, some air-conditioned shops and eateries around Times Square still had doors propped like open arms, beckoning passers-by to come into the cold.

“When the doors are open, it’s better for business,” says William Shalders, who manages Il Forno, an Italian restaurant that had its front door open; he said he wasn’t aware of the law.

It passed last fall, but first-time violators got only warnings until July 1. No violations or fines have yet been issued since the change.

Some New Yorkers haven’t waited for that to happen. Resident Dee Vitale Henle has taken it upon herself to close doors when she sees shops have them open.

“It still bothers me because we’re in a terrible energy crisis in this world,” she says.

There’s no exact measure of how much power goes out the door with air conditioning at city shops. The Natural Resources Defense Council has pegged the costs at up to $1,000 per summer for a typical business, which already pays summertime electric bills topping $2,200 a month. City sustainability officials have said closing doors at 10,000 businesses could cut 3,600 cars’ worth of emissions of carbon dioxide, a gas that contributes to global warming.

But some business owners say the city shouldn’t dictate what they do with their doors and on their own dime. And “Tonight Show” host Jimmy Fallon, for one, has suggested New York’s rule smacks of nagging, casting Democrat Bill de Blasio as “not only our mayor — he’s also our dad.”

The new law expands a pioneering 2008 measure that applied only to large chain stores and inspired a similar law in Washington, D.C., which also recently extended its measure to smaller shops and is still working to implement the law.

New York issued 308 warnings and 19 violation notices to chain stores last year, compared to 64 warnings and zero violations in 2014, according to Consumer Affairs Department data. Inspections, conducted in response to complaints and during regular patrols, rose from about 600 to 1,500.

Both New York and Washington have found enforcement complicated because inspectors couldn’t always immediately discern whether a given store met size criteria. The new laws eliminate those thresholds, while carving out exceptions for outdoor dining areas and deliveries.

Several business owners who say they make a point of closing doors have contacted the Brooklyn Chamber of Commerce with concerns about being penalized for not noticing if a delivery person or customer leaves a door open.

“I gotta get a ticket for that?” says Paul DiSpirito, who owns Lioni Italian Heroes, a Brooklyn sandwich shop.

“It’s not the government’s place to tell me to keep my energy bills low. Me, as a businessman, to survive, I have to keep my energy bills low,” he says.

To be sure, the city’s stray bursts of cool don’t go entirely unappreciated.

“It does feel good, that blast of air,” Jonathan Higbee, a photographer, said as he stood in a sweaty Times Square this week.

But for conservation’s sake, “I’m willing to give that up.”

(AP)