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Home Maintenance And Repair - 01500319

Humidifying - Operating the Humidifier

The water output of an appliance humidifier is based on continuous operation at standard rating conditions, not on the cycling of the residential heating system. Humidifiers without humidistat run continuously, while those with humidistat run continuously only when the controls are set to do so. The humidistat cycles the unit on and off as it senses different moisture needs caused by changes in indoor and outdoor conditions, including:

1. Amount of moisture absorbed by the house and its furnishings during the first few days of each humidifier season.

2. Amount of moisture generated by occupants and their activities, such as cooking and laundering.

3. Humidity level desired.

4. Changes in outdoor temperature, relative humidity, wind direction and velocity.


This article was written by Anne Field, Extension Specialist, Emeritus, with references from Ohio Extension bulletin Equipment Factsheet, and the Association for Household Appliance Manufacturers.

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