Bryan Smitherman said the conditions have been relentless.
"It's been very hot and muggy," he said. "These things are running all the time."
Smitherman lives in Durham County, where technicians report an unusually heavy workload.
"This is the busy season," said Kevin Kimbrough of Country Boy HVAC.
Experts say managing indoor humidity and avoiding drastic thermostat changes can help prevent systems from overworking. That matters, they note, because replacing an AC unit can be costly.
"I'm hoping I get a few more years out of them because they are very expensive to replace," Smitherman said.
Common issues include low airflow, bad capacitors, dirty filters, and clogged drain lines, which Kimbrough said account for many of his service calls.
"The main thing people can do to protect their units, change the filters, go outside, find the drain line. If it ain't dripping, it ain't cooling," he said.
Smitherman said he keeps his own drain lines clear.
"You can just use your vacuum cleaner or an air compressor to kind of blow a hose through that and make sure it blows a chunk of stuff out," he said.
As temperatures remain high, technicians say routine maintenance and attention to airflow can help homeowners avoid breakdowns and extend the life of their systems.
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