A humidistat or hygrostat is an electronic device analogous to a thermostat but which responds to relative humidity, not temperature. A typical humidistat is usually included with portable humidifiers or dehumidifiers. It can also be included with combined air cleaner or humidifier units to control a home's humidity level or any other indoor space.
Usage
Humidistats are used in a number of devices including
dehumidifiers,
humidifiers, and
microwave ovens. In humidifiers and dehumidifiers, the humidistat is used where constant relative humidity conditions need to be maintained such as a
refrigerator,
greenhouse, or
HVAC warehouse. When adjusting the controls in these applications the humidistat would be what is being set. In microwaves they are used in conjunction with
smart cooking one-button features such as those for
popcorn bag. Humidistats employ
but are not the same. A humidistat has the functionality of a
switch and is not just a measuring instrument like a hygrometer is.
For
accessed 27 October 2014, Chapter "Electronic Control Fundamentals", Section "Relative Humidity Sensor", pg 125
