Top-rated independent heating and cooling across central Arkansas and the Arkansas River Valley
Ice on the Indoor Coil
You open the closet or look at the indoor unit and there is a block of white ice on the coil, or the vents are blowing barely cool air while water drips on the floor. A frozen coil means your AC cannot move heat anymore. We repair frozen coils and the causes behind them across Arkansas, Louisiana, Missouri, Mississippi, Oklahoma, Tennessee and Texas. Turn the cooling off, set the fan to ON, and call us.
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- Open 7 days
- Written quote before work starts
Taking calls until 5:00 PM CT
Rock City Air Systems service team · field-reviewed before publishing
What Ice on the Coil Actually Tells Us
The indoor evaporator coil gets cold because refrigerant absorbs heat from the air passing over it. If not enough warm air moves across that coil, or there is not enough refrigerant to carry heat away properly, the coil surface drops below freezing. Condensation that should drain away turns to frost, then to solid ice. Once ice covers the fins, airflow stops almost completely and the problem accelerates. You get weak cooling, a long runtime that never satisfies the thermostat, and water where the drain pan overflowed. Ice is a symptom, never the fault itself. The repair is finding what starved that coil in the first place.'
Cause One: Airflow, The Cheapest Thing To Rule Out
Most frozen coils we see in this region start with restricted airflow. A filter loaded with dust is the usual suspect, especially in homes where pets shed year round. Closed or blocked supply vents count too, and so do returns behind furniture. On older homes with ducts run through hot attics, crushed flex duct or a disconnected trunk line can cut delivered air badly enough to freeze a coil in an afternoon. A dirty blower wheel or a failing blower motor does the same thing from the other side. Airflow problems are the least expensive family of causes, so we always check them first before touching refrigerant.'
Cause Two: Low Refrigerant, And Cause Three: Controls
If airflow checks out, we look at refrigerant charge. Low charge means low pressure in the coil, and low pressure means a colder coil that frosts. Low charge is almost always a leak, since refrigerant does not get used up. Adding more without finding the leak just buys you a few weeks. That work is refrigerant handling and it is not homeowner territory. Control faults make the third family: a stuck contactor, a bad thermostat calling for cooling nonstop, or a metering device that is not feeding the coil evenly. Humid weather in the river valleys makes every one of these show up faster.'
What You Can Safely Check Yourself
Shut the cooling off at the thermostat and set the fan to ON so room air can melt the ice. That can take several hours. Do not chip at it, and do not run a hair dryer near electrical parts. While it thaws, change the air filter if it is dirty. Walk the house and confirm supply vents and return grilles are open and not blocked by rugs or furniture. Step outside and clear grass clippings, leaves and mulch back from the outdoor unit. Check the breaker and the thermostat batteries. That is the whole safe list. Anything involving refrigerant, gas or high voltage needs a technician.'
What We Do Differently On A Frozen Coil Call
We arrive expecting to diagnose, not to guess. After the coil is clear, we measure actual airflow rather than assuming it, check static pressure across the coil and blower, and inspect the duct runs feeding the system. We take refrigerant pressures and temperatures and compare them to what the system should be doing on that day's conditions, then search for the leak if the numbers say low. We inspect the drain line and pan, because a frozen coil usually leaves water damage behind it. Then we tell you plainly what failed and what the air conditioning repair involves before any work starts.'
When it is time to book
Ice on the Indoor Coil — common questions
Can I just run the AC anyway until it thaws?
No. Running the compressor with a frozen coil can send liquid refrigerant back to it and cause expensive damage. Turn cooling off, leave the fan on so air melts the ice, and call us for the diagnosis.
How long does a frozen coil take to thaw?
With the fan running and the cooling off, usually two to six hours depending on how much ice built up and how humid the house is. Heavy ice on a whole coil can take longer. Do not chip at it.
It froze once and now cools fine. Do I still need someone out?
Yes. A coil does not freeze without a reason, and the reason is still there. It may be a filter you already changed, but it could be a refrigerant leak or a duct problem that will freeze again next hot week.
How it works
- Step 1
Tell us the symptom
Call or fill out the quote form and describe what the system is doing. Warm air, short cycling, water on the floor, a smell, a noise. That detail tells us what parts to load on the truck.
- Step 2
We diagnose on site
A technician checks the thermostat, the electrical side, airflow through the filter and coil, refrigerant behaviour and the ductwork. You hear what we found in plain language before anything gets replaced or repaired.
- Step 3
You approve the fix
We explain the repair, what it costs and what happens if you wait a season. Nothing gets done without your go-ahead, and we tell you honestly when a repair no longer makes sense.
- A real person answers
- Open 7 days
- Written quote before work starts
Why homeowners call us
- We know humid-climate systemsAcross the region the real enemy is moisture. Systems here run long hours pulling water out of the air, and that shows up as frozen coils, clogged drains and mildew smells. We diagnose for humidity, not just temperature.
- Mixed gas and heat pump workPlenty of homes we visit run a heat pump with gas backup, and the two have to hand off cleanly. We troubleshoot both sides, including defrost boards, reversing valves, ignitors and heat exchanger concerns.
- Attic ductwork is our daily breadMid-century homes often have ducts running through attics that hit brutal temperatures. Crushed runs, disconnected boots and leaking joints steal cooling before it reaches the room. We find them instead of blaming the equipment.
- Repair before replaceA capacitor, a contactor, a blower motor or a clogged drain line fixes a lot of the calls we take. We would rather fix what you have and tell you plainly when the numbers stop working.
- All major brands, gas & electricFrom Carrier and Trane to Lennox, Goodman, Rheem and Bryant, serviced independently.
- Straight answersNot worth fixing? We say that out loud, and often it saves you the visit fee.
About this guide
Checked everything on the list and it still acts up?
Tell us what you tried and what it did. The booking itself takes a minute.
- A real person answers
- Open 7 days
- Written quotes
- All major brands
- Gas & electric
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