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An instrument that measures and controls relative humidity. Also known as hydrostat.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


A device for measuring and controlling relative humidity.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved

humidistat, hygrostat

A regulatory device, actuated by changes in humidity, used for the automatic control of relative humidity.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
References in periodicals archive ?
Local thermostats and humidistats are assumed to schedule "unoccupied" status with appropriate relaxed temperature and humidity setpoints.
One solution is to place the humidistat in a location that's both easily accessible and provides an accurate reading of the patient's immediate environment.
The other systems also have a humidistat to control dehumidifiers or change system operation in response to the space-relative humidity level.
In addition to the thermostat, a humidistat controls the relative humidity of the core zone, providing humidification (by means of an electric steam humidifier placed in the main air loop) when relative humidity falls below 45% and dehumidification (by means of the cooling coil placed on the main air loop) when the relative humidity increases above 60%.
Many of the newer models come with a digital humidistat and automatic outdoor temperature compensation (such as the Honeywell No.
New plumbing, new electric, a Vantage lighting system, Mitsubishi central air, humidifier regulated by humidistat, and new carbon monoxide and smoke/heat detectors.
The problem was exacerbated by fitting an extractor fan controlled by the lights rather than a humidistat. Most showers were taken in daylight hours so the fan didn't operate.
Its digital controls include an automatic humidistat and a built-in hygrometer.
Does your MC system only control temperature (no humidistat built into the system)?