When it comes to ruling the market there is no competition for the Aprilaire humidifier model 550. This humidifier works on the popular evaporative principle and is one of the best and high quality humidification systems. These humidifiers are highly effective in any both summer and winter. These humidifiers require minimum maintenance and in return gives best quality performance. The main purpose of this humidifier is to protect you, your family and your home from getting affected by the dryness in the surrounding area. This humidifier can automatically provide the proper humidity required by you by changing its own settings.