Just wrapped up installing APCO-X UV air purification system in existing Carrier HVAC. System needed minimal duct modification. UV light positioned for maximum exposure to coil surface. Connected to 24V power supply with safety cutoff. This'll kill 99% of mold/bacteria on coils & improve IAQ significantly. Homeowner reported allergies & musty smell - this should help tremendously! Replaced air filter while there (was pretty dirty). Set reminder for UV bulb replacement in 2 yrs. Quick, clean job.