Why is there humidity in the room when air conditioner is cooling? Room feels damp.
The simple answer is no. What an air conditioner does, is cool air (obviously). When air is cooled however, it loses its ability to hold moisture. Therefore, the relative humidity (Water vapor/Capacity) of the air in the room will increase despite the fact that no moisture was added.
A room air conditioner will being putting out a haze if the air contains high levels of humidity. The mixture of cold and warm air will produce visible water vapor.
It depends on the BTU of the air coditioner, the cubic footage of space in the room to be cooled, and the temperature and humidity in the room. Under best conditions, an standard air conditioner can only cool a room to the mid 60's. Any colder than this causes the evaporator to ice over, clogging the air flow into the room, which causes the temperature to rise, even though the air conditioner is still running.
A window air conditioning unit placed in a windowless room ceases to be an air conditioner and instead becomes a dehumidifier, however, unless the condensed humidity (water) is removed from the room, it will simply be absorbed back into the room air as humidity.
It is the humidity from the air passing through the cooling coil that has condensed on the coil. By drainig it out the humidity inside the room is reduced and you feel cooler.
If the water vapor amount stayed the same, then the relative humidity would be greater.
The word, 'air conditioner' is a noun. The definition of air conditioner is a machine that controls the humidity and temperature of the air.
This is water that has condensed out of the room air on the evaporator coils of the air conditioner, and it is completely normal. If the humidity is high, one will see more water condensing and dripping from the air conditioner than when the room air is dry.
Dry Mode is a function that will reduce the humidity in the room. In this mode, as the air passes through the air conditioner the humidity will condense on the evaporator so that the air comes out drier. Reducing the humidity makes you feel cooler and more comfortable. Dry mode uses less power than cool mode.
A battery room may not require cooling, but it will require low humidity -- and for that you may need a cooling system or air conditioner.
An air conditioner mainly controls air temperature, but does also somewhat alter the humidity. A dehumidifier only affects the humidity, and not the temperature.
You will use more gas when your air conditioner is running.