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Home of the $0 FREE Service Call Club | 0% Interest for 24 Months

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(843) 708-8735
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Home of the $0 FREE Service Call Club | 0% Interest for 24 Months

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It’s no secret that summer heat in Charleston can crank up fast, and when your air conditioner isn’t doing its job, things get uncomfortable quickly. While most people think about filters, refrigerant, or thermostat problems when something goes wrong, there’s another part of the system that often gets overlooked: the sensors. These small components play a big role in how well your AC runs every day.

When AC sensors work like they should, your system knows when to turn on, how long to run, and when to shut off. If there’s something going wrong with one of those sensors, your system can start acting up, like turning on and off too often or not cooling enough. Taking the time to understand how your AC sensors work and what goes wrong with them can keep your system from slipping up when you need it most.

What Are AC Sensors?

Think of AC sensors as the eyes and ears of your air conditioner. They pick up on what’s happening in and around the system so it can adjust to the right settings and deliver balanced comfort in your home. Every time your AC kicks on or starts a cooling cycle, it relies on different sensors to measure things like temperature, humidity, and pressure. When those sensors send accurate information, your system runs smoothly. But if they send the wrong signals, everything can get thrown off.

Here are a few types of sensors you’ll typically find in a home AC setup:

1. Temperature Sensors: These are responsible for reading the temperature inside your home. They tell the AC when to start or stop cooling.

2. Humidity Sensors: These measure the moisture levels in the air. Some AC systems adjust how they run based on humidity to make the indoor air feel more comfortable.

3. Pressure Sensors: Found inside the system, these keep an eye on refrigerant pressure to help everything operate safely and efficiently.

4. Thermistor Sensors: These are located near the evaporator coils and regulate how cold the air gets before moving through your home.

Each sensor has a job to do. If just one starts misreading information, your AC system might make the wrong adjustments like cooling the air too much or not enough. Over time, this can lead to stress on internal parts and bigger, more expensive breakdowns.

Common Problems With AC Sensors

Most AC sensor issues don’t happen all of a sudden. They tend to build up quietly over time. A lot of the time, something simple like a sensor slipping out of place or getting dirty can lead to major comfort problems inside the home.

Here are some of the common problems we see with AC sensors:

1. Loose or misaligned sensors that can’t read the environment accurately

2. Buildup of dust or debris interfering with sensor function

3. Damaged or corroded wiring sending false signals

4. Sensors wearing out with age and normal use

One of the most frustrating symptoms of a sensor problem is short cycling, where your AC turns on and off too frequently. It uses more energy and never finishes a full cooling cycle. In other cases, a faulty sensor might keep the unit running too long or not long enough, which makes your home feel uncomfortable and unevenly cooled.

Let’s say a temperature sensor picks up heat from another appliance or a sunny window. The AC might mistakenly think the whole house is too warm and overcool the space. On the other side, if a thermistor is worn out and sending incorrect signals that it’s already cool enough, your unit might shut down early and leave you sweating. These small problems can easily spiral if ignored.

Signs Your AC Sensors Might Be Failing

Sensor problems can sneak up on you. They often start small but get worse over time. While you’re not expected to inspect each part of your system yourself, being aware of what to look for helps you take action before the problem grows.

Here are a few signs your AC sensors could be acting up:

– Your rooms feel too cold or too hot even though the system seems to be running

– The unit turns off and on multiple times an hour for no clear reason

– The AC never kicks on, even when the temperature inside rises noticeably

– Your energy bills are going up due to longer or more frequent cycles

One common issue we see is when homeowners set the thermostat, but inside the house it just doesn’t cool down like it used to. That’s often a result of poor sensor readings confusing the system. If your compressor or fans start working harder than they should, they’ll wear out sooner than expected.

Imagine it’s a bright, hot day in Charleston. You lower the thermostat expecting relief, only for the AC to start and stop in minutes. You sweat. The house doesn’t cool. What’s likely happened is that the thermistor near the coil is telling the system everything’s fine even though it’s not. These sensor issues disrupt comfort and load unnecessary strain on your system.

How Coastal Carolina Comfort Can Help

Dealing with failing sensors doesn’t have to mean sweating it out or guessing what went wrong. This is where an experienced AC contractor in Charleston really comes in handy. At Coastal Carolina Comfort, our trained technicians know exactly how to track down even the most hidden sensor issues and get your system running smoothly again.

If a sensor needs to be repositioned, recalibrated, or replaced, we’ll handle it quickly and thoroughly. We test every part to make sure it’s talking to the rest of the system correctly so you don’t end up facing the same problems again in a few weeks. Our team knows how Charleston’s weather affects HVAC systems and can help adjust settings and schedules to fit the unique needs of your home.

We’re familiar with every nook and cranny these sensors can hide in, so we don’t miss a thing. One visit from a skilled technician can help you avoid breakdowns during the peak cooling season.

Keeping Your AC in Top Shape

Avoiding sensor problems starts with some simple steps and a little professional care. Having your AC looked at once a year goes a long way. When our team visits for a check-up, we inspect everything from wires to filters to make sure the system is balanced and sensors are reading accurately.

Keep the unit and the space around it clean. Dust, leaves, and pollen can clog parts that need to breathe and operate freely. Over time, buildup can trigger sensor misreads. This is something that slips under the radar for many homeowners but creates big issues later.

Another good habit is to watch how your system behaves day to day. If rooms cool unevenly or turn chilly too fast, trust your instincts. These little problems can lead to bigger ones, especially once the heat kicks into high gear.

Sensors might be small, but their impact is huge. When they’re working properly, you enjoy quiet, steady comfort throughout the summer. If they’re not, your whole system suffers. At Coastal Carolina Comfort, we take care of sensor problems early so one faulty reading doesn’t turn into a long, hot summer.

If your home in Charleston is dealing with AC sensor troubles, professional support can keep your system running the way it should. A trusted AC contractor in Charleston can pinpoint sensor issues and get cooling performance back on track. Count on Coastal Carolina Comfort to handle the job right and keep your comfort going strong through the hottest months ahead.

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Hvac Repair In Summerville
HVAC

The Summerville HVAC Maintenance Checklist

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

Derrick Hall January 28, 2026
Hvac Repair Vs Replacement
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HVAC Repair vs. Replacement

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Do I fix it, or do I replace the whole thing? It’s not an easy decision. Repair feels like the cheaper option—until you’re repairing again six months later. Replacement feels like the responsible choice—until you see the price tag. And everyone from your neighbor to your brother-in-law has an opinion. At Coastal Carolina Comfort, we’ve guided thousands of Lowcountry homeowners through this exact decision. We’ve seen people waste money repairing systems that should have been replaced years ago. We’ve also seen people replace perfectly good equipment because someone talked them into it. This guide will give you the framework to make the right decision for your situation—not based on sales pressure, but on facts, math, and what actually makes sense for your home and budget. The 50% Rule: Your Starting Point The most reliable rule of thumb in the HVAC industry is simple: If the repair costs more than 50% of what a new system would cost, replace instead of repair. Here’s why this works: The Math Behind the Rule Let’s say a new HVAC system for your Summerville home costs $8,000 installed. Using the 50% rule: Repair cost under $4,000: Repair is likely the better value Repair cost over $4,000: Replacement makes more financial sense But this isn’t just about today’s repair. It’s about what comes next. A system that needs a $3,500 repair today is likely to need another significant repair within 1-2 years. That’s the nature of aging equipment—when major components fail, others are usually close behind. So that $3,500 repair might actually cost you $3,500 + $1,200 + $800 over the next two years. Suddenly you’ve spent $5,500 and still have an old, inefficient system. When to Adjust the Rule The 50% rule is a starting point, not an absolute. Adjust based on: System age: For systems under 8 years old, you might stretch to 60-70% before replacing—they likely have more good years ahead. For systems over 12 years old, consider replacing at 30-40% of replacement cost. Repair history: If this is the first major repair on a well-maintained system, lean toward repair. If it’s the third repair this year, lean toward replacement regardless of cost. Component involved: Some repairs (capacitor, contactor, fan motor) are normal wear items that don’t indicate broader system failure. Others (compressor, evaporator coil) often signal the beginning of the end. The Age Factor: How Old Is Too Old? System age is the second most important factor in your decision. Average HVAC Lifespan National average: 15-20 years with proper maintenance Summerville reality: 12-16 years is more typical Why the difference? Our systems work harder. A Summerville AC runs 8-9 months per year, often 12+ hours per day during summer. Compare that to a system in Minneapolis that might run 4 months per year. More operating hours means faster wear. Age-Based Decision Framework Under 8 years old: Almost always repair unless the cost exceeds 50% of replacement. These systems have significant life remaining. 8-12 years old: Evaluate carefully. Major repairs may be worthwhile, but start planning for eventual replacement. This is a good time to begin saving. 12-15 years old: Lean toward replacement for major repairs. The system is in its final years, and repair money is often better invested in new equipment. Over 15 years old: Replace for any significant repair. Even if the repair is relatively affordable, you’re likely facing additional failures soon. The efficiency gains alone often justify replacement. The Warranty Consideration Most HVAC systems come with: 5-10 year compressor warranty 5-10 year parts warranty 1 year labor warranty (sometimes extended by the installer) If your system is still under warranty, repair almost always makes sense—your out-of-pocket cost is limited to labor and any non-covered parts. Check your paperwork or call your installer to verify warranty status before making any decisions. The R-22 Refrigerant Problem If your system uses R-22 refrigerant (also called Freon or HCFC-22), this single factor may make your decision for you. What Happened to R-22 R-22 was the standard air conditioning refrigerant for decades. However, due to its ozone-depleting properties, the EPA phased it out: 2010: No new R-22 systems could be manufactured 2020: Production and import of R-22 banned entirely This means all R-22 available today is either recycled or reclaimed from decommissioned systems. Supply is limited and shrinking every year. The Cost Impact R-22 prices have skyrocketed: 2010: Approximately $10-15 per pound 2020: Approximately $50-75 per pound 2026: $100-200+ per pound depending on availability A typical residential AC system holds 6-12 pounds of refrigerant. If your R-22 system develops a leak, you’re looking at: Leak repair: $200-$1,000+ depending on location Refrigerant recharge: $600-$2,400+ for a full charge Total cost: Often $1,000-$3,000+ for a single repair And here’s the kicker—if it leaks once, it will likely leak again. You could face these costs repeatedly. How to Know If You Have R-22 Check the data plate on your outdoor unit. Look for: “R-22” or “HCFC-22” = R-22 system (consider replacement) “R-410A” or “Puron” = Modern refrigerant (repair may make sense) If your system was installed before 2010, it almost certainly uses R-22. Systems installed 2010-2015 could be either. Systems installed after 2015 are virtually all R-410A. Our Recommendation If you have an R-22 system that needs any refrigerant-related repair, replace

Derrick Hall January 28, 2026

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