Evaporator Coil Service
EVAPORATOR COIL SERVICE
Frozen, dirty, or leaking indoor coil killing your cooling? We clean, repair, or replace it and get the cold air — and the airflow — back. Flat-rate, 24/7 live.
4.9 · 3,569 reviews (2 profiles)
Verified Google reviews
4.9★ on Google
3,569 reviews · 2 profiles
24/7 Emergency
Call for current availability
Licensed & insured
LA Master Plumber #1874
North Louisiana
Ruston to Monroe
Flat-rate pricing
Quoted before we start
Overview
The Coil That Actually Makes the Cold
Your evaporator coil is the indoor half of your AC — it's where the refrigerant absorbs heat and humidity out of your air. When it freezes over, clogs with dust and biofilm, or springs a slow leak, cooling drops off, bills climb, and you can end up with water where it shouldn't be. Mark Johnson & Sons diagnoses and services evaporator coils across Ruston, Monroe, West Monroe, and Grambling.
A frozen coil is almost always a symptom of something else — low refrigerant from a leak, restricted airflow from a dirty filter or blower, or a failing metering device. We find the real cause instead of just thawing it and handing you a bill. On our long, humid summers a coil runs wet for months, and that moisture is exactly what dust, mold, and corrosion feed on.
What goes wrong with a coil
- It freezes — low charge or weak airflow drops the coil below 32°F and it ices over, choking cooling and risking the compressor
- It clogs — dust and biofilm cake the fins, insulating the coil and cutting capacity and airflow
- It leaks — formicary "pinhole" corrosion, common on aluminum coils in humid climates, lets refrigerant escape
- The drain backs up — a plugged condensate line overflows the pan and stains ceilings or floods a closet
Clean, repair, or replace
A dirty coil almost always comes back with a proper deep clean — pulled, treated, and rinsed to restore capacity and airflow. A leaking coil is a bigger decision: a matched replacement coil is quoted flat-rate, and if the AC is already 10-plus years old or the compressor is weak, we'll show you the math on replacing the coil versus the whole system. We service coils in every major brand — Carrier, Trane, Lennox, Goodman, Rheem, York, American Standard, Bryant, and Amana.
What Mark Johnson & Sons does differently
We don't guess. Every frozen or weak-cooling call gets a full check — airflow, static pressure, refrigerant charge, blower, and metering device — so the fix holds instead of freezing up again next week. When we replace a coil we pull a real vacuum, weigh in the correct charge, and verify the temperature drop across the coil before we leave. Ask about our service savings agreement plans — the Spring AC tune-up includes cleaning and inspecting the coil, which is the single best way to keep it from clogging or freezing in the first place.
Free quote
Book a coil diagnosis
Frozen, weak, or dripping? Tell us what your AC is doing and we'll find the real cause and quote it flat-rate before any work.
4.9★
24/7
Emergency
Free
Quote
Current coupons
View allWAIVED
Service call waived with any coil repair
Diagnostic fee applied to the repair.
Expires 12/31/2026
$150 OFF
Evaporator coil replacement
Standard pricing. Must mention at booking. One offer per household.
Expires 12/31/2026
15% OFF
Coil repairs for service members
Requires active service savings agreement. Cannot combine with other offers.
Expires 12/31/2026
Mention coupon when booking. One offer per household.
Warning signs
Signs of an evaporator coil problem
These point straight at the indoor coil — worth catching before the compressor pays for it.
Ice or frost on the indoor coil, line set, or air handler
AC runs constantly but the air isn't cold
Weak airflow from the vents
Water pooling or a musty smell around the indoor unit
Refrigerant that keeps running low despite recharges
Higher bills with no change in how you run the system
Short cycling tied to the coil freezing and thawing
A ceiling stain or overflowing drain pan under the air handler
The house never quite dehumidifies, even when it hits temperature
Fix the cause
A frozen coil is a symptom — we find why.
Thawing a coil without fixing what froze it just buys you a day. We check airflow, charge, and the metering device so it stays fixed — and so your compressor doesn't pay the price.
Not a bandaid
Root cause
Across Ruston, Monroe, West Monroe, and North Louisiana.
The Process
How we service an evaporator coil
On the truck
Professional tools, parts, and diagnostics — every call.
Diagnose the real cause
Frozen or weak cooling gets a full check — airflow, static pressure, refrigerant charge, blower, and metering device — so we fix the cause, not just the symptom.
Thaw & inspect
If the coil is iced, we thaw it safely and inspect for dirt buildup, corrosion, and leaks.
Clean or leak-test
A dirty coil gets a proper deep clean; a suspected leak gets pinpointed with electronic detection so you're not guessing.
Flat-rate options
Clean, repair, or replace — you get honest options and a flat-rate price before any work.
Restore & verify
We confirm airflow, charge, and temperature drop across the coil so you get full cooling back.
Pricing
How We Price Evaporator Coil Service
Flat-rate, quoted before work. Service call waived with the repair. Service members get 15% off.
Flat rate, quoted before we start
You get the full price for the job up front — not an hourly meter you watch climb. You approve it before a tool comes out of the truck.
The quote is the price
It doesn't move once work begins. If something unexpected turns up behind a wall or under a slab, we stop and talk it through with you before going further.
Service members save 15% on every repair
Service savings agreements start at $189 a year and take 15% off all plumbing, heating, and cooling repairs, with priority scheduling on every call. The Premium Service Savings Agreement Plan adds same-day service and drops after-hours charges entirely.
Financing available
Bigger jobs — a system replacement, a repipe, a sewer line — can be financed through GoodLeap. Apply online in a few minutes.
Every job is priced for your home and what it actually needs — tell us what's going on and we'll get you a firm number, free and with no obligation.
Service Savings Agreement Plans
Two plans. Whole-home peace of mind.
From $189 a year, service members get 15% off every plumbing, heating, and cooling repair, two complete HVAC tune-ups, a free plumbing and drain check-up, and priority scheduling on every call.
- 15% off repairs
- Priority scheduling
- 2 HVAC tune-ups/yr
- After-hours discounts
- $25 savings certificate
- Guaranteed flat-rate
Service Savings Agreement Plan
$189/year
Everything it takes to keep the house maintained and your repairs discounted.
Each additional HVAC unit is $89/year
Premium Service Savings Agreement Plan
$389/year
Everything in the Service Savings Agreement Plan, plus no after-hours charges, no travel fees, and same-day service.
Each additional HVAC unit is $89/year
Questions? (318) 319-0220
1-year term · does not auto-renew
FAQ
Evaporator Coil Service FAQs
Why does my evaporator coil keep freezing?
A coil freezes when it can't absorb enough heat — usually from restricted airflow (dirty filter, blower, or coil) or low refrigerant from a leak. We find which one it is. Thawing it without fixing the cause just means it freezes again, and running a frozen system can wreck the compressor.
Can a dirty coil be cleaned, or does it need replacing?
Most dirty coils can be deep-cleaned to restore capacity and airflow — replacement is only needed when the coil is leaking or badly corroded. We'll tell you honestly which situation you're in and quote it flat-rate.
Why do evaporator coils leak?
In humid climates like North Louisiana, formicary corrosion — tiny pinhole leaks caused by household chemicals and moisture — is a common culprit, especially on aluminum coils. A leaking coil can sometimes be repaired at a fitting, but pinholes in the coil itself mean replacement.
How much does a coil replacement cost?
Evaporator coil replacement is quoted flat-rate and depends on the system and refrigerant type. If the AC is older or the compressor is also weak, we'll show you the math on replacing the coil versus the whole system.
Should I replace just the coil or the whole AC?
If the system is under about 10 years old and otherwise healthy, a matched replacement coil is the smart money. Past 12 years — or on an old R-22 system where refrigerant is expensive and scarce — putting that kind of money into a coil often isn't worth it against a new, more efficient system. We lay out both numbers so you decide.
How long does a coil replacement take?
Most cased-coil replacements are a same-day job — a few hours to pull the old coil, braze in the matched replacement, pull a vacuum, and weigh in the charge. If we have to order a specific matched coil it may be a day or two out, but we'll tell you up front.
Why is water leaking around my indoor unit?
Usually a clogged condensate drain. The coil pulls a lot of moisture out of Louisiana's humid air, and that water drains through a line that can plug with algae and sludge. We clear the line and pan, and if the coil itself is iced and dripping as it thaws, we track down why it froze.
Does the service savings agreement cover coil cleaning?
Yes. The Spring AC tune-up under the $189/year Service Savings Agreement Plan includes cleaning and inspecting the coil, plus 15% off any repair and priority scheduling — the best way to keep a coil from clogging or freezing in the first place.
Can I clean the evaporator coil myself?
You can rinse the outdoor condenser coil, but the indoor evaporator coil sits inside the air handler and usually has to be accessed or pulled to clean properly — and the fins bend easily. A real deep clean also lets us inspect for corrosion and leaks at the same time, which a spray-and-hope never catches.
How fast can you come out if my AC is frozen up?
Same-day is standard during business hours, and we answer live 24/7. Turn the system to fan-only to start thawing the coil and give us a call — running a frozen AC risks the compressor. An after-hours surcharge applies on top of the repair.
Related services
Related cooling services
A coil problem often shows up alongside these — we handle them on the same call.
Available Around the Clock
Emergency?
We answer 24/7.
Burst pipe, water heater out, sewer backup? Real plumbers pick up — no answering machines. Mark Johnson & Sons Plumbing serves North Louisiana any time, day or night.
LA Master Plumbing #1874 · Backflow Cert #28131 · Master Natural Gas Fitter #LMNGF9062 · State Contractors #35794