Seasonal pollen and the return side of the system
Pollen in Keller arrives in waves, and the return ducts catch it. Once it is inside the system it recirculates, settles on surfaces and shows up as that fine film on furniture a day after dusting. Cleaning the returns, the supplies and the blower compartment, then keeping a good filter in place, is what actually changes it. Families dealing with spring and fall allergy flares usually notice the difference in the first week.
