How Does a Humidistat Work

Winters are the most dreaded of all seasons. Not only you have to bear the wrath of cold winds, but you also have to combat the extreme dryness in the air. The less amount of water vapor in the air makes it uncomfortable to stay even in the warm interiors of your home or office. A good solution to this problem would be to install a humidifier to add the required amount of water vapor in the air. However, it is necessary to control the amount of water vapor you add to the air. This is where a humidistat comes into play. This little device allows you to control the amount of humidity to maintain a desired or relative humidity.

Humidistat Working

To understand its working, you will have to understand the working of various components that are involved in a humidistat. Humidistat comprises a series of metallic conductors made from sensitive element. These metallic conductors are capable of sensing even the slightest variations in the humidity inside the room. These conductors are connected to a relay amplifier. The humidity variations cause a resistance to flow through the metallic conductors. This resistance is then measured with a relay amplifier.

A humidistat either works as a standalone device to control humidifiers or it is often used in collaboration with the central heating or air conditioning system. In that case, the humidistat works in conjunction with a thermostat. The humidistat controls the ON/OFF cycle of the air conditioner by sensing the humidity in the air. You may find the humidistat controls located next to the thermostat on the main floor or you may find it separately in the duct.

Although, humidifier adds water vapor to your home, it is not desirable to have large amount of damp air inside your home. This damp air is taken out with humidistat fan or vents. A desired amount of humidity can always be maintained by adjusting the humidistat according to the external climate conditions.

Humidistat Setting

Humidistat setting is dependent upon the following factors:

• Number and type of occupants inside the home.
• Outside air temperature.
• Type of insulation in the house.
• Vapor barriers.
• Efficacy of weather stripping.
• Type of windows and doors (including frames and jams).
• Whether storm windows and doors are installed or not.

As you can see, there are so many variables involved, hence it is very difficult to predict the ideal humidistat setting that will function for every household.

Humidistat should be set at 65%, if the outdoor temperature exceeds 20º F. If you have thermostat and humidistat working together, then you might want to set the temperature of your thermostat as well. When thermostat and humidistat work together, thermostat controls the working of air conditioner by sensing the heat in the room, whereas a humidistat controls it according to the level of humidity in the room. Thus, if there is more humidity in the air than heat, the working of air conditioner will be triggered by a humidifier. In normal temperature conditions, you should set your humidistat at 75% and thermostat at 80º F. Make requisite changes by evaluating the climate conditions in your specific geographic location. Do not set it on lower level, as it could lead to too much of dryness, while setting it too high can cause indoor precipitation.

Humidistat setting is of prime importance to experience maximum comfort during any season. Hence, make sure you choose a proper setting.