HVAC Maintenance Checklist for York County, SC

Every month or two

• Check the filter and replace it when it looks gray. A clogged filter is behind a large share of frozen coils, tripped limit switches and weak airflow.
• Walk past the outdoor unit. Keep grass, leaves and mulch a couple of feet away and never stack anything on it.
• Glance at the thermostat: right mode, sensible schedule, fresh batteries if it takes them.

Fall, before the first cold night

• Run the heat for ten minutes on a mild day so the first cold night is not the first test. A dusty smell for a few minutes is normal; a burning-plastic or gas smell is not.
• Replace the filter and clear the space around the furnace or air handler.
• Gas furnace: make sure the exhaust and intake pipes outside are clear, and that nothing is stored near the burner. Test every carbon monoxide alarm and replace any that has reached its stated end of life.
• Heat pump: clear the outdoor unit and expect it to steam and pause on cold damp mornings; that is the defrost cycle. Check that the thermostat is not sitting in emergency heat.
• Book a professional heating tune-up before the busy season if the system is more than a few years old.

Spring, before the first hot week

• Replace the filter and switch the thermostat program to cooling.
• With the power to the outdoor unit off, rinse the outdoor coil gently with a hose from the inside out. Do not use a pressure washer and do not bend the fins.
• Find the condensate drain line (a PVC pipe near the indoor unit) and flush it so the summer's water has somewhere to go. A blocked drain is the usual cause of water around the air handler.
• Test cooling on a mild day and listen: a new rattle, hum or click is worth a call before July.
• Book a cooling tune-up; spring slots are easier to get than June ones.

What a professional tune-up covers

A thorough visit checks the refrigerant charge, tightens electrical connections, tests the capacitors and contactor, cleans the indoor and outdoor coils, clears the condensate drain, checks the blower and airflow, and calibrates the thermostat. On a gas furnace it also inspects the burners, the flame sensor, the ignitor, the inducer and the heat exchanger, and checks for combustion gases where they should not be. Ask for the list of what was checked and any readings taken; a good company writes them down.

When to call a professional

• Any gas smell: leave the house and call the gas provider from outside first.
• A breaker that trips more than once, ice on the lines or the indoor coil, water around the indoor unit, or no heating or cooling after the checks above.
• Anything that needs the refrigerant circuit opened, the gas valve adjusted or the heat exchanger inspected. Those are licensed-contractor jobs in South Carolina. SC LLR issues the HVAC Installer and Repairer license and has an online lookup; a replacement also needs a permit where required (see the cost guide).

Repair pages with every listed company and tap-to-call: York, Rock Hill, Fort Mill, Clover, Tega Cay, Indian Land. Heating-season reading: furnace repair and heat pumps. We list companies, not services, and we have not checked which jobs each one takes. Call to confirm a company works on your type of system before you book.