HVAC in South Carolina runs a long, wet cooling season almost everywhere, and a real heating season only as you climb toward the foothills. Coastal condensers sit in salt and corrode at the cabinet, the fins, and the electrical lugs. Midlands attics cook air handlers above brick ranches until a clogged condensate line overflows and stains a ceiling that looks like a roof leak. The Upstate still needs heat on a hard night, including houses whose heat strips or furnaces have sat quiet since spring. Say coast or interior before you describe the noise.
If cooling died, say whether the outdoor unit is silent, short-cycling, or buried in ice on the copper line. A packed filter after pollen, or a collapsed return, can imitate a failed compressor. Ask what gets ruled out first. If there is no heat, say whether anyone smells combustion and whether the flue has been part of the look. A house without heat in the Upstate on an ice night is urgent. The same night on a sea island may be uncomfortable and still not the same equipment story.
Replacement should be sized for the house you have, not copied off the old nameplate. Ask about the ducts: reused, sealed, or resized. Two-story houses with a roasting upstairs are a duct problem as often as a unit problem. Matched indoor and outdoor equipment belongs in the description. A new condenser on a tired coil should be explained as its own path. Humidity is half the job. Cold, clammy air in a Lowcountry July is not success.
Ask about the float switch, the pan, and where the condensate goes. On the coast, ask what salt does to the outdoor cabinet and whether the disconnect is already crusted. Inland, ask about attic heat and filter rhythm through pollen. Maintenance should leave you a list of what was opened. If the bath fans dump moisture into the same attic the air handler lives in, say that, because the equipment is being asked to dry a house the fans are soaking.
Say heat or cooling, dead or weak, and name the town. HVAC in South Carolina is salt and humidity on the coast and a longer heat load as you drive inland and up. Call the number on this page.