Cracked Evaporator Coil – AC Repair in San Marcos
A cracked evaporator coil is a serious fault because it lets refrigerant escape — the system slowly loses its ability to cool no matter how much freon is added. For San Marcos homeowners, understanding the cause helps decide between a repair and a full replacement.
What cracks an evaporator coil
- Formicary (pinhole) corrosion — formic acid created from everyday household VOCs (cleaners, paint, air fresheners, new furniture) eats microscopic holes in the copper. It’s the leading cause on modern coils.
- Vibration and metal fatigue after years of operation.
- Age, or an occasional factory defect in the coil.
Signs of a cracked or leaking coil
- Cooling that weakens over weeks, and longer run times.
- A hissing or bubbling sound near the indoor unit.
- Ice forming on the coil or refrigerant lines.
- Rising energy bills, and the tell-tale “it needs more freon every season.”
Repair or replace?
A few pinholes can sometimes be sealed, but a cracked coil usually needs the coil itself replaced. If the system is still under warranty, a coil replacement is often the right call. If it’s older and out of warranty — especially if it still uses the older R-22 refrigerant — replacing the system can be the smarter long-term investment.
Why a professional leak test matters
Refrigerant is sealed under pressure and must be recovered and handled by an EPA-certified technician. We pressure- and leak-test the coil to confirm the crack, measure the loss, and give you both repair and replacement options honestly — with no pressure to over-buy.
Suspect a cracked evaporator coil in San Marcos? Prime Air Solutions will leak-test it and explain your options. Call (619) 759-5111.
Frequently Asked Questions
Can a cracked evaporator coil be repaired?
Sometimes a small pinhole can be sealed, but a genuinely cracked coil usually needs replacement. We test it and tell you honestly whether a repair will hold.
Is it worth replacing just the coil or the whole AC?
If the system is newer or under warranty, replace the coil. If it’s older, out of warranty, or uses R-22, replacing the whole system is often more cost-effective.
What is formicary corrosion?
It’s pinhole corrosion caused by formic acid that forms when copper reacts with common household chemical vapors (VOCs). It’s the most common reason modern coils develop leaks.
How long does an evaporator coil last?
Many last 10–15 years, but indoor air quality and humidity affect that. Good ventilation and limiting strong household chemicals near the air handler can extend coil life.
Why does my AC need refrigerant every year?
Refrigerant is in a sealed loop — if it keeps dropping, it’s leaking, often from the evaporator coil. Repeated recharging only masks the problem and adds cost.