“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 Frozen / Ice on Lines
Frozen AC Coil? Here's What to Do — and Why It's Freezing.
Ice on your copper line, evaporator coil, or air handler means refrigerant is dropping below 32°F. Two root causes: restricted airflow OR low refrigerant. Switch the system OFF + FAN ON, then call us.
Why Treasure Coast Trusts Us
Reasons Homeowners & Captains Pick Maritime Air Co.
5-Star Rated
Verified Google reviews
Licensed & Insured
Class-A CAC1824400
Family Owned & Operated
Treasure Coast residents
Residential · Commercial · Marine
Full-spectrum HVAC
Written Estimates
Approved before work begins
Photo-Documented Work
Warranties registered for you
Chamber of Commerce
St. Lucie County member
Step 1: Turn the system OFF, fan ON
Running a frozen AC damages the compressor and can rupture refrigerant lines. Switch the thermostat to OFF and the fan switch to ON. The blower will thaw the coil in 1–2 hours.
Cause 1: Dirty air filter (most common)
A clogged filter starves the coil of warm return air. Coil temperature drops below 32°F and ice forms. Replace the filter; if it's been less than 30 days, the real problem is deeper (blower, ducts, or refrigerant).
Cause 2: Dirty blower wheel
Florida dust and pet hair coat the squirrel-cage blower wheel, cutting airflow 40–60%. The coil ices over even with a fresh filter. We pull and wash the blower wheel as part of our $89 deep clean.
Cause 3: Low refrigerant from a leak
Low charge drops evaporator temperature below freezing. Recharging without finding the leak is a 3-month fix. We pressure-test with nitrogen, electronic leak-detect, repair, and recharge to factory spec.
Cause 4: Closed supply vents / duct restriction
Closed vents in unused rooms, crushed flex duct, or undersized returns all restrict airflow. We use a manometer to measure static pressure and identify the restriction.
Cause 5: Failing TXV / expansion valve
The thermostatic expansion valve meters refrigerant into the coil. A stuck-closed TXV starves the coil and causes freezing. We diagnose with superheat and subcooling readings and replace when 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
View all projects Example HVAC Scenarios
Real installs and repairs we've completed across the Treasure Coast.
Coil Cleaning
Evaporator Coil Pull & Deep Clean — Port St. Lucie
Port St. Lucie, FL · Residential Split System
Trane Installation
Trane XV20i Installation — Fort Pierce
Fort Pierce, FL · Trane XV20i + TAM9
Trane Installation
Trane XR16 + Heat Pump Installation — Port St. Lucie
Port St. Lucie, FL · Trane XR16
FAQ
Common Questions
Should I turn off a frozen AC?+
Yes — switch the thermostat to OFF and the fan to ON. Running FAN ONLY for 2 hours thaws the coil safely. Continuing to run the system in COOL mode while frozen can damage the compressor and rupture refrigerant lines.
Why does my AC keep freezing up?+
Repeat freezing always traces to restricted airflow (dirty filter, dirty blower wheel, closed vents, undersized return) or low refrigerant charge from a slow leak. We diagnose both during a single service call.
Will a frozen AC fix itself?+
It will thaw on its own, but the underlying cause won't fix itself — and continued operation damages the compressor. Call us so we can find and repair the root cause.
Don't run a frozen AC — call (772) 236-4277.
Call (772) 236-4277 or schedule online. Class-A licensed across the Treasure Coast.