Of all humidity control devices, a whole house furnace humidifier will give the most control over a house's environment. These machines are usually of  humidification capacity that allows you to cover up to 2500 to 3000 square feet of home space from one central location id the house. A whole house furnace humidifier is connected to the central heating system of the home... the forced air furnace. Humidifiers like these are placed and installed in the furnace's ventilation ducts and humidity the air as it passes through it and will then circulate all around the house and improve or balance the air quality content. Whole house furnace humidifiers are most commonly mounted in a by-pass position on the furnace. This mean some of the hot air exiting the furnace will be passed across the humidifier to better pickup humidity from it, then the same, buy humid air is after discharged on the cold air return side of the furnace. Every home humidification systems like explained here are equipped of a humidistats to control the water addition. | 
