Coconut Creek AC Repair: Why Your AC Runs But Won’t Cool

Estimated Read Time: 11 minutes

If your AC is running but not cooling, you are not alone—especially in humid South Florida where systems work overtime. In this guide, you will learn the seven most common reasons for weak cooling, the safe DIY checks you can try, and when to call ECM Air Conditioning for rapid, professional help. We also explain how to prevent repeat breakdowns with our multi‑point tune‑ups and priority plans.

1) Thermostat settings or sensors are off

Start with the simplest check. Make sure the thermostat is set to Cool and the fan is on Auto, not On. A fan set to On blows air constantly, even when the compressor is not cooling. Also verify the setpoint. If your home is at 78 and the setpoint is 78, it will not call for cooling.

Modern thermostats rely on internal temperature sensors. If the thermostat is in direct sunlight, near a kitchen, or close to a supply vent, it can read hotter or colder than the room. That false reading causes short cycling or long runtimes with little cooling. In some homes around West Palm Beach and Boca Raton, we see thermostats mounted on exterior block walls that heat up in the afternoon and mislead the system.

Quick checks you can do now:

1. Confirm Cool mode and Auto fan.
2. Lower the setpoint by 3 to 5 degrees.
3. Replace thermostat batteries if applicable.
4. Make sure the schedule is not overriding your setting.

If the display is blank, the unit may not be getting power, which is covered further below. A professional can recalibrate, relocate, or replace the thermostat and verify low‑voltage controls.

2) Dirty filters, coils, or blocked return airflow

South Florida’s high pollen and dust load can clog filters quickly. A dirty filter chokes return airflow, which lowers the volume of air across the evaporator coil and reduces heat transfer. You will feel weak airflow at the vents and notice longer runtimes.

Beyond the filter, coils and blower wheels collect debris. We routinely find matted evaporator coils and impacted blower blades in homes near the beach where salt and fine sand accelerate buildup. A clogged coil can even freeze, turning your air handler into a block of ice and stopping cooling entirely.

DIY steps:

1. Replace or wash your filter. Use the correct size and orientation.
2. Check for blocked returns behind furniture or drapes.
3. If you see ice on the refrigerant lines, turn the system off for 4 to 6 hours to thaw, then replace the filter and restart.

If icing returns or the coil is dirty, schedule a professional coil cleaning. ECM technicians also sanitize drain pans and can add anti‑algae tablets to reduce microbial growth.

3) Low refrigerant charge or a refrigerant leak

If your system is low on refrigerant, it will run without delivering enough cooling. Signs include warm supply air, hissing at the indoor unit, and icing. Only a licensed HVAC technician should measure superheat, subcooling, and pressures to diagnose low charge correctly. Charging by “feel” or guessing leads to poor efficiency and compressor damage.

Important facts:

1. Many systems use R‑410A. Older R‑22 systems are no longer produced and are costly to recharge.
2. A proper repair includes leak detection, not topping off. We use electronic detectors, UV dye, and nitrogen testing.
3. Manufacturer parts warranties often cover specific components for up to 10 years. When applicable, ECM secures qualifying warranty parts for you.

If your unit is 10 to 15 years old and leaking, it can be smarter to replace instead of chase leaks. We provide free second opinions on replacement units and a free 99‑point A/C system engineering assessment for installations.

4) Frozen evaporator coil or failed blower motor

When an evaporator coil freezes, cooling stops. Causes include low airflow from a dirty filter, underspeed blower, or low refrigerant. After thawing, if ice returns within a day or two, the underlying fault remains.

A weak or failed blower motor also creates symptoms that feel like “AC running but not cooling.” The outdoor fan may spin and the condenser may hum, but indoor airflow is low. ECM technicians measure motor amperage, static pressure, and temperature differential across the coil to isolate the cause.

What you can do:

1. Thaw the coil fully and replace the filter.
2. Make sure supply vents are open throughout the home.
3. If airflow remains weak, schedule service to test the blower motor and capacitor.

5) Outdoor unit issues: condenser coil, fan, or clearance

Heat removed from your home must be dumped outside at the condenser coil. If the outdoor coil is clogged with lint, grass, or salt film, the system loses capacity. In coastal cities like Pompano Beach and Deerfield Beach, salt spray can coat fins quickly.

The outdoor fan must also move the right amount of air. Bent blades, failing bearings, or a weak capacitor reduce airflow. And without adequate clearance around the unit, hot air recirculates. We recommend at least 24 inches of clear space on all sides and no hot dryer vent blowing at the unit.

Safe homeowner steps:

1. Turn off power and gently hose from inside out if the coil is dirty on the surface.
2. Trim plants back to allow airflow.
3. If the fan squeals, rattles, or will not start, turn the system off and call for service to prevent compressor damage.

6) Duct leaks, poor insulation, or incorrect duct design

Leaky or undersized ductwork wastes cooling and drives up bills. In older homes from Fort Lauderdale to Coral Springs, we find return leaks pulling hot attic air into the system. That makes supply air warmer and adds humidity, so it feels muggy even with the thermostat set low.

Common duct problems we fix:

1. Disconnected or crushed flex ducts.
2. Leaky boots and seams, often visible as dust streaks.
3. Unbalanced supply causing hot rooms and temperature swings.

Our team performs static pressure tests, camera inspections, and air temperature differential checks. We seal with mastic, repair connections, and can redesign for proper airflow. If your ducts were never sized for your current system, a right‑sized redesign can transform comfort.

7) Power, safety switches, or condensate drain shutdowns

If your air handler runs but cooling stops and starts, look for safety trips. A clogged condensate line can trigger a float switch and shut your system down to prevent water damage. Algae growth is common in South Florida and can block the drain during summer.

What to check safely:

1. Reset the AC breaker if it has tripped. If it trips again, call for service.
2. Inspect the condensate line outside. If it is not dripping during cooling, it may be clogged.
3. Empty the drain pan if the float switch is activated. Do not bypass the switch.

During maintenance, ECM installs anti‑algae tablets and clears the drain. Our plans also include disinfectant treatments for coils and drain pans where applicable.

How to troubleshoot safely before you call

You can often rule out simple issues in minutes:

1. Verify thermostat settings and replace batteries.
2. Replace the air filter and open all supply vents.
3. Check that your outdoor unit is clear of debris and that the fan spins.
4. Inspect the condensate drain for clogs and the air handler for ice.
5. Confirm the breaker is on and the disconnect is seated.

If these steps do not restore cooling, continued operation can damage the compressor. Schedule a diagnostic. ECM provides upfront pricing with a No Surprises guarantee, and for qualifying equipment under manufacturer parts warranty, we secure warranty parts.

When repair makes sense vs. when to replace

Repair first when the system is young, has a minor fault, or is under warranty. Examples: a bad capacitor, a clogged drain, or a small control issue. Replace when the system has a major refrigerant leak, a failing compressor, or repeated breakdowns and high energy bills.

Consider replacement if:

1. Your unit is 12 to 15 years old and uses R‑22.
2. Repair costs exceed 25 to 30 percent of replacement.
3. Comfort is poor even after duct and airflow fixes.

ECM offers free second opinions on replacement units, financing options, and a free 99‑point A/C system engineering assessment for installations. That assessment verifies sizing, duct static pressure, airflow, and energy performance before we install.

Prevent breakdowns with multi‑point maintenance

Heat, humidity, and salt air punish AC systems. Preventive maintenance is the best way to keep performance high and energy costs low. ECM performs detailed multi‑point tune‑ups, including:

1. Check thermostat calibration and settings.
2. Measure refrigerant pressures and superheat/subcooling.
3. Measure compressor and fan motor amp draw.
4. Clean or replace filters and sanitize drain pans.
5. Install anti‑algae tablets and clear condensate lines.
6. Inspect electrical connections, capacitors, and contactors.
7. Measure air temperature differential and static pressure.

Our Watt Saver maintenance plans include seasonal tune‑ups, priority service, same‑day appointments, and a 15 percent discount on repairs. Plans available in select areas include 21‑Point or 29‑Point tune‑ups in summer and winter, plus one free diagnostic evaluation.

Why homeowners in South Florida choose ECM

Local experience matters. We have served Palm Beach, Broward, and St. Lucie since 1985, where afternoon storms, lightning, and algae growth create unique AC issues. ECM operates more than 200 employees with a fleet of 127+ stocked service vehicles, so we respond fast. Many emergency calls are reached in 60 minutes or less.

What you can expect:

1. Upfront pricing with a No Surprises guarantee.
2. 24/7 emergency service and same‑day repairs.
3. 100 percent satisfaction guarantee.
4. Free in‑home estimates and free second opinions on replacements.
5. Advanced diagnostics and energy analysis for durable fixes.

Whether you are in West Palm Beach, Boca Raton, Fort Lauderdale, or Port St. Lucie, our technicians bring the right parts, tools, and know‑how to get your cooling back quickly and keep it efficient.

Special Offers for Faster, More Affordable Repairs

• $90 A/C Service Call for new customers. Schedule today and get expert diagnostics at a great price.
• On‑Time Promise: We will be there on time or your $90 service call is free.
• Plan Member Perks: 15% discount on repairs with our Watt Saver maintenance program, plus priority scheduling.
• Warranty Advantage: For qualifying equipment under the manufacturer’s parts warranty (typically under 10 years), warranty parts are free.

Call (561) 473-9463 or schedule at https://ecmservice.com/. Offers subject to terms and availability in your area.

What Homeowners Are Saying

"ECM installed a new AC condenser and air handler in our apartment. Scheduling was easy. Installation was fast and efficient. We are very pleased with their work."
–ECM Customer, West Palm Beach

"The technician, Miguel, was very knowledgeable when he explained that we needed a new air conditioner and why. He answered all our questions. The crew sent to remove the old system and install the new one was terrific... It was a great experience. I highly recommend ECM to everyone."
–ECM Customer, Broward County

"A new AC unit was installed by a very knowledgeable technician the day after I was told I needed a new one. Very satisfied with the service I received."
–ECM Customer, Boca Raton

Frequently Asked Questions

Why is my AC running but not cooling?

A few common causes are dirty filters, low refrigerant, a frozen coil, duct leaks, or incorrect thermostat settings. Try a new filter and confirm Cool mode with Auto fan. If cooling does not return, schedule a professional diagnosis.

Can low refrigerant damage my system?

Yes. Low charge reduces cooling, overheats the compressor, and can cause icing. A licensed technician should find and fix the leak, then charge to manufacturer specs using superheat and subcooling.

How often should I change my filter in South Florida?

Every 30 to 60 days for standard filters, more often with pets or renovations. High pollen, humidity, and salt air load filters quickly and restrict airflow.

What temperature should I set my thermostat to in summer?

Most homes balance comfort and efficiency at 75 to 78 degrees with Auto fan. Use ceiling fans to feel cooler at the same setpoint.

What does a professional AC tune‑up include?

ECM’s multi‑point tune‑ups include thermostat checks, refrigerant measurements, electrical testing, filter service, coil and drain sanitation, anti‑algae tablets, and airflow tests. Plans include seasonal visits and repair discounts.

The Bottom Line

When your AC is running but not cooling, simple fixes like a clean filter or correct thermostat setting can help. If problems persist, you may have a frozen coil, low refrigerant, duct leaks, or safety shutdowns. For fast, expert AC repair in West Palm Beach and nearby cities, call ECM.

Ready to Get Cool Again?

Call (561) 473-9463, chat or schedule at https://ecmservice.com/. New customers: ask for the $90 A/C Service Call and our on‑time promise. Prefer priority care and 15% off repairs? Enroll in a Watt Saver maintenance plan today.

Call (561) 473-9463 or book at https://ecmservice.com/ for same‑day AC repair. Mention the $90 A/C Service Call for new customers and our on‑time promise. Stay cool today!

About ECM Air Conditioning

ECM Air Conditioning is South Florida’s trusted HVAC, plumbing, and electrical team serving Palm Beach, Broward, and St. Lucie counties since 1985. We operate with more than 200 employees and a fleet of 127+ service vehicles. Licenses: CAC-1822777, CFC-048260, EC-0001843, WARRANTY-80196. We offer 24/7 emergency service, upfront No Surprises pricing, and a 100% satisfaction guarantee. Our technicians, not salespeople, provide free in-home estimates, free second opinions on replacements, and advanced diagnostics, including a 99-point A/C system engineering assessment for installations.