The evaporator coil is the "cold" part of the system located inside your Indoor Air Handler. As air is blown across this copper and aluminum coil, the refrigerant inside absorbs the heat from your room. Our High-Efficiency Systems use blue-fin or gold-fin coatings on these coils to improve water drainage and prevent corrosion. Keeping this coil clean is vital for maintaining a healthy Delta T and preventing odors. If you experience a "frozen" indoor unit, it’s usually because of a dirty evaporator or low refrigerant. We provide Coil Cleaner and Replacement Filters to help you avoid these issues. You can find detailed coil specs in our Technical Data section. It is the core of the indoor cooling process.