AC Not Cooling? Step-by-Step Troubleshooting for Homeowners

By Briggs Heating
on
Homeowner checking outdoor AC unit for airflow and blockages

Is the air in your home feeling more like a muggy summer afternoon than a cool oasis? When the AC stops cooling, frustration sets in fast. You need answers, and you need them right now. Briggs Heating’s emergency hvac team knows exactly how stressful a hot house can be—especially when every minute counts.

Before you reach for the phone, let’s break down why this happens and what you can do. Sometimes, a simple fix is all it takes. Other times, a deeper issue lurks beneath the surface. Either way, knowing the basics will save you time, money, and maybe a few beads of sweat.

Why AC Units Stop Cooling

Air conditioners are like orchestra conductors—when every part works in harmony, the result is pure comfort. But when one instrument falters, the whole performance suffers. Here are the most common reasons your AC might not be cooling:

  • Clogged or dirty air filters: Like breathing through a scarf on a hot day. The airflow gets choked, and your system can’t keep up.
  • Thermostat issues: Settings get bumped, batteries fade, or sensors misread temperatures.
  • Power supply problems: Tripped breakers or loose wiring can stop everything cold.
  • Low refrigerant: Refrigerant is the lifeblood of your system. If it leaks or runs low, cooling stops.
  • Dirty or blocked outdoor unit: If leaves, dirt, or backyard toys crowd around your outdoor condenser, heat gets trapped inside.

Quick Safety Checklist 🛑

Before you touch a thing, safety first. Always:

  • Turn off the power at the breaker before opening panels.
  • Never touch wiring or terminals if you’re unsure—electric shock is no joke.
  • If you smell burning or see smoke, leave the area and call for emergency hvac help right away.
  • Follow manufacturer troubleshooting steps in your owner’s manual.
  • If water is pooling, watch for slip hazards and avoid electrical contact.

Basic DIY Checks for Homeowners

You don’t need a toolkit the size of a garage to check the basics. Here’s what you can do:

1. Check Thermostat Settings

  • Make sure it’s set to “cool.”
  • Lower the temperature a few degrees below the current room temp.
  • Replace batteries if the display is blank or faded.

2. Inspect Circuit Breakers

  • Go to your breaker panel.
  • Look for any tripped breakers (they’ll be in the middle, not fully "on" or "off").
  • Gently flip the breaker off, then back on.

3. Change or Clean Air Filters

  • Pull out the filter. If it’s gray or packed with dust, swap it for a new one.
  • Replace filters every 1–3 months, or more often if you have pets or allergies.

4. Clear Outdoor Unit Blockages

  • Walk outside and check the condenser.
  • Clear away leaves, branches, or debris.
  • Make sure there’s at least 2 feet of space all around the unit.

Advanced Signs: When It’s More Than a Quick Fix

Sometimes, the problem hides deeper. Watch for these warning signs:

  • Ice buildup: Frost on the coils means airflow problems or low refrigerant.
  • Strange noises: Grinding, rattling, or buzzing often signals failing parts.
  • Leaks: Water or refrigerant pooling near the unit is a red flag.
  • Warm air blowing: If your vents push out air that’s not cold, something’s off.
  • Short cycling: The unit turns on and off rapidly, never cooling the house.

If you notice any of these, it’s time to pause DIY steps and consider calling an emergency hvac professional.

DIY vs. When to Call a Pro 🛠️

Where’s the line between a homeowner fix and a job for Briggs Heating? Here’s how to tell:

DIY-Friendly Issues

  • Thermostat settings or battery changes
  • Resetting tripped breakers
  • Replacing filters
  • Clearing outdoor debris

Call a Pro If:

  • AC won’t turn on, even with power and correct settings
  • You see ice, hear odd noises, or find leaks
  • The unit trips the breaker repeatedly
  • Airflow is weak or nonexistent
  • The system smells burnt or electrical
  • You suspect low refrigerant (EPA guidelines require licensed pros for handling refrigerants)

Your safety matters most. If you’re ever unsure, play it safe—professional help is just a call away.

What Pros Do When They Arrive

Briggs Heating technicians don’t just guess—they follow proven steps, using tools and training that go beyond DIY basics.

  • Full system inspection: Checking thermostats, wiring, and safety switches
  • Airflow testing: Measuring pressure and temperature at vents
  • Refrigerant check: Using EPA-approved gauges to find leaks or low levels
  • Electrical diagnostics: Testing capacitors, contactors, and motors for failure
  • Manufacturer guidelines: Verifying with brand-specific troubleshooting procedures
  • Repair and replacement: Fixing or replacing parts as needed
  • Safety compliance: Meeting local code requirements and industry standards (ASHRAE, EPA, and NFPA)

Prevention: Maintenance & Filter Changes 🧰

A little effort now saves a lot of hassle later. Here’s how to keep your AC humming:

  • Change filters regularly: Every 1–3 months, and more during heavy use.
  • Schedule annual maintenance: A professional tune-up catches issues before they become emergencies.
  • Keep units clear: Trim bushes and clear debris around outdoor units.
  • Check thermostat batteries: Once a year, or at the start of every season.
  • Listen for changes: Odd noises, new smells, or poor airflow? Don’t ignore them.

According to ENERGY STAR and the U.S. Department of Energy, regular maintenance can extend your system’s lifespan and boost efficiency.

Costs & Time Factors

Wondering what to expect if you call for AC Repair near you?

  • Simple fixes (filters, thermostat) take 10–30 minutes.
  • More complex repairs (electrical, refrigerant) can take 1–3 hours.
  • Emergency hvac calls may involve extra time for diagnostics or sourcing parts.

Costs vary by region, system age, and part availability. Always ask for an estimate before work begins.

When It’s an Emergency 🚨

Not every AC problem is a crisis, but some situations demand immediate help:

  • No cooling during heat waves: Especially risky for young children, elderly, or those with health challenges.
  • Burning smells or sparking: Shut down the unit and evacuate if needed.
  • Water pooling near electrical components: Risk of shock or fire.
  • Repeated system shutdowns: Can indicate dangerous electrical issues.
  • Refrigerant leaks: Exposure can be harmful, and repairs require certified handling.

Briggs Heating offers 24 hour emergency service for both residential and commercial customers. Your comfort—and safety—are our priority.

FAQ: Quick Answers for Homeowners

Why is my AC running but not cooling the house?

Common causes: dirty filters, thermostat issues, low refrigerant, or blocked outdoor unit.

Can I add refrigerant myself?

No. Refrigerant handling is regulated by the EPA and should only be done by certified professionals.

How often should I replace my AC filter?

Every 1–3 months, depending on usage, pets, and allergy concerns.

What temperature should I set my thermostat in summer?

The U.S. Department of Energy recommends 78°F (26°C) when home, higher when away to save energy.

Local & Seasonal Considerations

  • Pollen season: Change filters more often in spring and fall.
  • Storms and wind: Check outdoor units after severe weather for debris or damage.
  • High humidity: Consider a dehumidifier to help your system cool more efficiently.
  • Energy audits: Periodic home energy audits can catch insulation leaks that make your AC work harder.

The bottom line? A quick check can solve many cooling problems, but never hesitate to call Briggs Heating when your comfort or safety is on the line. Our emergency hvac team is ready, day or night.

Call Briggs Heating now — or reach us anytime at  877-748-7966 .

Heating issues? Briggs is ready to help. | Speak to an Expert 877-748-7966