Portable Humidifier Malfunctions

Problem: Portable, belt-type humidifier doesn’t run, or continues to run for extended periods.

Background: Portable humidifiers, which use wide belts of porous material partially submerged in a tank reservoir to evaporate moisture into the room, usually will have a variable speed control (controlling how fast the belt turns) as well as an automatic humidity control. Some units have colored pilot lights; one which signals when the cord is plugged in and the variable speed control is in the operational range, and another which signals when the unit has shut down automatically because the water level in the reservoir has gotten too low.

What to do: If the unit does not run, make sure it is plugged in to a live outlet. If it does not turn on, it may be because the humidistat is set below the relative humidity of the room, or because the humidistat has not had enough time to adjust to the conditions in the home (this may take several hours). If the home and furnishings are exceptionally dry, the humidifier may operate for an extended period of time. After proper humidity is reached, the operation time of the unit will be shorter. If the humidifier continues to run excessively, check for open doors or windows, as well as for an open fireplace damper. The air escaping up the chimney can cause 2 or more complete air changes in the home per hour; the more air changes, the greater the humidity requirements.

Special advice: For the most effective humidification, keep doors open to all rooms to be humidified. Do not place the unit with its back grille too near drapes or curtains. Air movement could pull drapes against the grille and cut off air flow, resulting in possible damage to the humidifier or the drapes. For maximum efficiency, the evaporator belt should be replaced at least once a season, or more often under severe conditions. The unit should be cleaned periodically, and emptied and cleaned at the end of the season. Also, once a season, put 2 to 4 drops of oil in any oiling tubes provided on the fan motor.

Helpful hint: All humidifiers containing water for extended periods will eventually develop odors. Periodic cleaning, and the use of water treatment tables, can help prevent this. For very persistent odors, use 2 tablespoons of chlorine bleach diluted in 1 gallon of water to clean the tank and the evaporator belt.