Is Hot Cathode better than Cold Cathode?
In the uppermost vertical section of your plenum both hot and cold cathode tubes suffer diminished effectivness based on cooler temperatures. We overcompensate with excessive UV-C wattage to get a maximum kill without ozone. Hot cathode is more effective than cold cathode when installed at the condenser coil. Cooler temperatures were known to cause hot cathode UV lamps to dim a little, but the new OxyCat sleeve holds the temperature of the bulb while it does its job, the second method of air purificaiton.
