Ice formation on an evaporator coil is always a symptom of saturation temperature dropping below 0°C (32°F). The two primary thermodynamic causes are severely restricted airflow (fouled air filters or clogged blower wheel) and low refrigerant mass flow (slow gas leak or starved expansion valve).
⏱️ 7 min read
📊 Intermediate
⚙️ Split AC, Ductable Central, Cold Rooms
Evaporator Coil Freezing & Thick Ice Accumulation: Root Causes & Fixes
Ice formation on an evaporator coil is always a symptom of saturation temperature dropping below 0°C (32°F). The two primary thermodynamic causes are severely restricted airflow (fouled air…
⚠️ Identified System Fault Symptoms
- Thick block of ice covering indoor copper cooling fins
- Water dripping excessively from indoor unit casing
- Reduced airflow volume from the supply vent
- Suction line copper sweating heavily or freezing all the way to outdoor unit
Interactive Diagnostics
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