But, if the fan is set to On, the moisture on the refrigerant coils does not even get the chance to drain away
You might be inviting a ton of humidity into your dwelling without even knowing it by setting your AC control appliance fan to On instead of Auto. On and Auto are the two settings for your fan, and the difference between ON & AUTO basically comes down to when the fan blows. In the Auto position, the fan only blows during an AC appliance cooling cycle. In the On position, the fan blows basically always, even when the AC appliance is not cooling. This also means that it uses more energy & has a greater expense to run. To better understand how a fan affects indoor humidity, first you should guess what the AC appliance fan does & where it is located. If you have a split system AC appliance, you entirely have two fans in your AC appliance. One fan for your outdoor unit & 1 fan for your indoor unit. Your indoor unit fan sits straight behind the cooling coils & is essentially responsible for pushing air through the ducts & into your dwelling. Essentially, the On setting is not permitting your AC to properly dehumidify your dwelling. Your AC has two particular functions. It cools your dwelling & dehumidifies it, and when sizzling air from inside your dwelling is pulled into your indoor unit, it passes over especially cold refrigerant coils. Those cooling coils absorb the warmth & moisture from the air. Then, that nippy dry air is pushed back into your dwelling. If the fan is set to Auto, that moisture collects & sits on the refrigerant coils. Once the fan shuts off in between cooling cycles, that moisture has plenty of time to slide off the coils & drain away outdoors. But, if the fan is set to On, the moisture on the refrigerant coils does not even get the chance to drain away. Because the fan blows essentially always, most of the moisture evaporates & gets blown back into your dwelling.