The Summerville HVAC Maintenance Checklist That Prevents 90% of Repairs Regular HVAC maintenance prevents up to 90% of common repairs and extends system lifespan by 5-7 years. Summerville homeowners should perform monthly tasks (filter checks, vent clearing, thermostat monitoring), seasonal tasks (condensate drain treatment, outdoor unit cleaning, refrigerant line inspection), and schedule professional tune-ups twice yearly—in spring before cooling season and fall before heating season. The Lowcountry’s extreme humidity, extended cooling season, and airborne particulates demand more frequent maintenance than national guidelines suggest. A well-maintained system runs more efficiently, breaks down less often, and keeps your home comfortable year-round. Introduction: The Cheapest Repair Is the One You Never Need Here’s a number that should get your attention: 90%. That’s the percentage of HVAC repairs that could have been prevented with proper maintenance. Nine out of ten service calls we make in Summerville are for problems that didn’t have to happen. Clogged filters that caused compressors to overheat. Condensate drains that backed up and flooded ceilings. Capacitors that failed because coils were too dirty to dissipate heat. Refrigerant leaks that started as minor corrosion nobody caught. Every one of these repairs cost the homeowner hundreds—sometimes thousands—of dollars. And every one of them was preventable. At Coastal Carolina Comfort, we’ve maintained HVAC systems across the Lowcountry for over a decade. We’ve seen what neglect does to equipment in our climate. We’ve also seen homeowners who follow a simple maintenance routine go 10+ years without a single major repair. This guide gives you that routine. It’s specifically designed for Summerville’s climate—not generic advice written for somewhere with mild summers and low humidity. Follow this checklist, and you’ll dramatically reduce your repair bills, extend your system’s life, and stay comfortable no matter what the Lowcountry weather throws at you. Why Summerville Systems Need More Maintenance Before we dive into the checklist, let’s talk about why maintenance matters more here than almost anywhere else. The Extended Cooling Season In Minneapolis, an AC might run 4 months per year. In Summerville, we’re cooling 8-9 months—sometimes longer. That’s twice the operating hours, twice the wear, and twice the opportunity for problems to develop. A system that runs from April through November accumulates wear equivalent to nearly two years of operation in a milder climate. Maintenance intervals need to reflect that reality. The Humidity Factor Summerville’s average humidity hovers around 70-80% year-round. During summer mornings, it regularly exceeds 90%. This humidity: Forces your system to work harder (dehumidification uses significant energy) Creates ideal conditions for biological growth in drain lines and on coils Accelerates corrosion on electrical components and refrigerant lines Causes condensate drain clogs—one of the most common service calls we see Related: Learn how Summerville’s humidity damages HVAC systems Airborne Particulates Between pollen season (which feels like it lasts 8 months here), coastal salt air, and general Lowcountry dust, your system filters more particulates than systems in cleaner environments. Filters clog faster, coils get dirtier, and airflow restrictions develop more quickly. The Bottom Line National maintenance guidelines assume average conditions. Summerville doesn’t have average conditions—we have extreme conditions. Your maintenance routine needs to account for that. Monthly Maintenance Tasks These quick tasks take 10-15 minutes and should become habit. Do them on the same day each month—the first Saturday, the day you pay your mortgage, whatever helps you remember. 1. Check and Replace Your Air Filter This is the single most important thing you can do for your HVAC system. A clogged filter: Restricts airflow, forcing your system to work harder Causes evaporator coils to freeze Leads to compressor overheating and failure Increases energy consumption by 5-15% Reduces indoor air quality How to check: Locate your filter (return air grille, air handler, or dedicated filter slot) Remove the filter and hold it up to light If you can’t see light through it clearly, replace it If it’s visibly gray or caked with debris, replace it immediately Summerville-specific guidance: During peak cooling season (May-September), check weekly and replace every 30-45 days During shoulder seasons, check monthly and replace every 45-60 days During pollen season (spring), you may need to replace every 2-3 weeks After storms or high-wind events, check immediately Filter recommendations: Use pleated filters rated MERV 8-11 for best balance of filtration and airflow Avoid fiberglass filters (minimal filtration) and ultra-high MERV ratings (can restrict airflow) Buy filters in bulk—you’ll use 8-12 per year in Summerville 2. Clear Supply and Return Vents Blocked vents disrupt airflow balance and force your system to work harder. Monthly walkthrough: Check all supply vents (where air blows out) for obstructions Check all return vents (where air is pulled in) for blockages Move furniture, curtains, rugs, or stored items that block airflow Vacuum vent covers to remove dust buildup Ensure all vents are open (closing vents doesn’t save energy—it creates pressure imbalances) 3. Monitor Thermostat Performance Your thermostat is the brain of your HVAC system. Small issues here cause big problems. Monthly checks: Verify the display is clear and responsive Confirm the temperature reading seems accurate (compare to a separate thermometer) Check that the system responds when you adjust settings Replace batteries annually (or when the low battery indicator appears) For smart thermostats, ensure WiFi connection is stable Warning signs: Temperature swings greater than 2-3 degrees from setpoint System not responding to setting changes Blank or flickering display “Auxiliary heat” running frequently (for heat pump systems) 4. Listen and Observe Your system tells you when something’s wrong—if you’re paying attention. Monthly awareness check: Listen for unusual noises (grinding, squealing, banging, clicking) Notice any unusual odors from vents Feel for weak airflow or temperature inconsistencies Watch for water around the indoor unit Check for ice on refrigerant lines (visible at the outdoor unit) Related: Know the 5 warning signs your AC is about to break down Seasonal Maintenance Tasks These tasks should be performed quarterly or at the start of each season. They’re more involved than monthly tasks but still manageable for most homeowners. Spring: Prepare for Cooling Season Complete these tasks in