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An instrument that measures and controls relative humidity. Also known as hydrostat.


A device for measuring and controlling relative humidity.

humidistat, hygrostat

A regulatory device, actuated by changes in humidity, used for the automatic control of relative humidity.
References in periodicals archive ?
The other systems also have a humidistat to control dehumidifiers or change system operation in response to the space-relative humidity level.
During the cooling season, even if the indoor air relative humidity is not mechanically controlled (there is not a humidistat that senses the indoor conditions and activates the system response), the air, which is a mixture of outdoor air and recirculated indoor air, is partly dehumidified while passing through the cooling coil of the fan coil.
This control method can be implemented by using a humidistat wherein a humidity sensor measures the RH in the controlled space and heating of the air is initiated by the controller when the RH goes above a pre-set value.
Moreover, the humidistat and fan control let you meet any comfort need, as this humidifier can evaporate up to four gallons of water a day.
Lamb adds, "Even better, attach a humidistat that will automatically turn the fan on when moisture reaches a specific level.
Standard features include a humidistat, stainless steel construction, round-collar duct connections, washable filters, inorganic desiccant rotor and PTC heaters for long life.
Air-to-air heat exchangers controlled by a humidistat are one way to ameliorate the introduction of outside air into a heated home.
A Purchase a good humidistat and place it in the center of your manufacturing operation.
8 |degrees~ Celsius and then fed through humidistat and heat exchangers which are directed by individual room controls.