“My highest recommendations for Devon and the Maritime Air team — thorough, honest, and on time. They explained everything in plain language and didn't push any unnecessary upsells.”
Spencer Fuller
May 2026
AC Troubleshooting · Treasure Coast
AC Running But Not Cooling? Here's What's Wrong.
When your AC blows air but won't drop the temperature, it's almost always one of 8 specific failures. We've diagnosed thousands across the Treasure Coast — here's exactly what we look for, what it costs, and what you can check yourself before calling.
Why Treasure Coast Trusts Us
Reasons Homeowners & Captains Pick Maritime Air Co.
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Class-A CAC1824400
Family Owned & Operated
Treasure Coast residents
Residential · Commercial · Marine
Full-spectrum HVAC
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1. Dirty condenser coil (most common)
Salt air, palm pollen, and lawn debris choke condenser coils within months on the Treasure Coast. A coil that can't reject heat will run constantly without dropping indoor temperature 5°F below outdoor. We rinse from inside-out with non-acid coil cleaner — a 30-minute fix that often solves the entire problem.
- Check: is the outdoor unit hot to the touch and the fan running?
- Try: gently rinse the OUTSIDE of the fins with a garden hose (turn power off first)
- If that doesn't restore cooling within 60 minutes — call us
2. Low refrigerant from a slow leak
Florida humidity corrodes aluminum coil joints. A 20% low charge cuts cooling capacity in half. We pressure-test with nitrogen, electronic leak-detect, repair the leak, and recharge to factory spec. Recharging without finding the leak is a 6-month fix at best.
- Symptom: ice on the copper line at the outdoor unit
- Symptom: bubbles or hissing near the indoor coil
3. Failed run capacitor
The single most common HVAC failure in Florida. A bulged or weak capacitor prevents the compressor and condenser fan from starting, even though the thermostat is calling. $185–$285 to replace, takes 20 minutes.
4. Frozen evaporator coil
Restricted airflow (dirty filter, closed vents, dirty blower wheel) drops coil temperature below freezing. The coil ices over and stops absorbing heat. Solution: turn the system to FAN ONLY for 2 hours to thaw, replace the filter, and call us to clean the blower wheel and check for additional restrictions.
5. Failed contactor
The contactor is a low-voltage relay that sends 240V power to the compressor and fan. Pitted or welded contacts prevent the outdoor unit from starting. $195–$295 to replace, 30-minute fix.
6. Thermostat issue
Dead batteries, loose wiring, or a failed thermostat won't signal the outdoor unit. We swap in a known-good thermostat to verify before condemning anything else.
7. Failing compressor
Compressor failure presents as a humming outdoor unit that won't start, or a system that cools weakly. Most compressors are under 10-year manufacturer warranty — we diagnose and process the claim for you.
8. Ductwork leaks or collapse
Returns pulling 130°F attic air or supply runs leaking into the attic can make a working AC feel useless. We pressure-test ducts with a duct blaster and seal or replace as needed.
Reviews
What Treasure Coast Customers Say
5.0
37 Google Reviews
Google
“Devon has provided thorough maintenance and excellent service. Truly family-owned care — they treat your home like it's their own. Highly recommend for Treasure Coast homeowners.”
Oh Canada
March 2026
“Working with Devon on my HVAC system was a great experience from start to finish. Fair, clean install, and the system has been running perfectly through Florida summer heat.”
David Alker
February 2026
Our Work
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Real installs and repairs we've completed across the Treasure Coast.
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Port St. Lucie, FL · Trane XR16
FAQ
Common Questions
Why is my AC running but not cooling?+
The most common causes in Florida: a dirty condenser coil restricting heat rejection, low refrigerant from a slow leak, a failed run capacitor, a frozen evaporator coil from airflow restriction, or a thermostat calling for cool but not signaling the contactor. We diagnose all five in a single service call.
Can I fix it myself?+
You can change the air filter and clear obvious debris from the outdoor unit. Beyond that, refrigerant work requires EPA 608 certification and the wrong diagnosis (e.g. recharging a system with a leak) wastes money and damages the compressor. Free phone diagnostic — we'll tell you what's safe to try first.
How much does it cost to fix an AC that won't cool?+
Capacitor replacement: $185–$285. Contactor: $195–$295. Refrigerant recharge with leak repair: $385–$895. Compressor replacement: $1,400–$2,800 (often warranty-covered if under 10 years). $89 in-home diagnostic applied to any repair.
How fast can you respond?+
Same-day across the Treasure Coast — typically 2–4 hours from call. Captain's Comfort Club members get priority dispatch.
Get cool today — same-day Treasure Coast dispatch.
Call (772) 236-4277 or schedule online. Class-A licensed across the Treasure Coast.