Heat domes mean extra hard work for the heating, ventilation and air-conditioning systems that give New Yorkers relief from the sweltering summer.

The costs are two-fold: Your electric bill will rise because your AC is working overtime to beat back the heat, and the added workload may trigger breakdowns and even shorten the system’s life span.

You will especially notice these problems if your system is more than 10 years old. HVAC systems generally last about 15 years or so, but they often begin to lose efficiency after 10 years, according to the Department of Energy.

A heat dome’s prolonged hot spells can even cause an AC system to overheat after it has been running full-tilt for an unusually long time. An overheated system often will stop working.

Smart steps

Help your AC thrive despite summertime blues:

• Make sure the filter is clean, the condensate line is clear of algae, and other components are in good running condition.

• The system will welcome a break, so try to dial back the thermostat to let the AC turn off or at least not work as hard.

• Be realistic. AC systems are built to cool a building to a temperature 15 or 20 degrees cooler than the air outside. An afternoon with 95-degree temperatures outdoors translates into a household temp of 75 or 80 – safe enough but maybe not the chill thrill you desire.

AC problems in Manhattan? Premier HVAC in Brooklyn answers calls promptly and efficiently.