Keeping evaporator coils clean is one of the most impactful — and most overlooked — steps in routine HVAC maintenance, and the Nu-Calgon Evap-Fresh No-Rinse Aerosol (part number 4166-75) makes it faster and easier than any other product on the market. The self-rinsing foaming formula penetrates deep into coil fins to loosen dirt, dust, and organic buildup, then drains away naturally with the unit's condensate flow — no water flushing, no scrubbing, and no rinsing required. The result is a cleaner coil, better airflow, improved system efficiency, and a noticeably fresher lemon scent that customers appreciate long after the technician leaves. What sets the 4166-75 apart from standard coil cleaners is its inverted-spray valve, which allows the can to spray at full pressure in any orientation — including completely upside down. This makes it the go-to choice for cramped air handler compartments, tight mini-split indoor units, and any installation where getting the nozzle into position is half the battle. Compatible with residential and light commercial air conditioner evaporator coils, mini-split indoor units, and refrigeration and freezer evaporative coils, the Evap-Fresh is genuinely versatile across a full day of service calls. Ready to use straight from the can with no dilution or pump equipment needed, it's the kind of product that earns a permanent spot in every HVAC technician's service bag. Each pressurized 18 oz aerosol can is sold individually and also available by the case of 6 for high-volume operations. Manufactured by Nu-Calgon, a trusted name in professional HVAC chemical products since 1936. Disconnect power to the unit before applying. Read all label directions before use.