Maintenance – Bypass and Fan Powered Units

To operate safely, effectively, and efficiently, humidifiers require periodic maintenance. With proper maintenance, a humidifier will provide optimum levels of humidification for the home and workplace for many years. By industry averages, with proper maintenance humidifiers can last an average of 12-15 years. According to the Mayo Clinic, humidifiers not maintained properly can become a breeding ground for bacteria and mold, contributing to health problems the humidifier is intended to suppress. Such health problems include asthma, allergies, flu-like symptoms or even lung infections. Humidifiers can also consume large amounts of water without delivering the desired humidification – if they are not checked and maintained regularly.

Consult the owner’s manual for specific instructions for maintaining your humidifier.
The general maintenance procedures for Whole House and Portable humidifiers are described below. Owner’s Manuals for many popular humidifiers can be downloaded directly from our website off each Product’s page.

Check the Humidistat and Water Flow
Humidistats (the humidifier controllers) have a test setting that enables you to run the humidifier in a test mode to confirm proper operation. Some advanced thermostats also include a humidistat. Check the owner’s manual for your humidifier or advanced thermostat for instructions.

Be sure that the blower fan of the furnace is running. Set the humidistat to the test position and confirm that water is flowing through the unit. If water is not flowing, consult the owners manual for Troubleshooting Tips.

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Replace the Water Panel and Clean Components
Bypass and fan-powered humidifiers contain a water panel (also called evaporator pad) that is made of porous material through which water flows. Warm air from the heating system also passes through the panel, picking up moisture. The water that is not absorbed by the air drains out of the unit.

The water panel can become clogged with scale and mineral deposits that restrict the flow of water and air. It needs to be checked monthly when the humidifier is in use. The water panel should be replaced at the beginning of each heating season and whenever scale and mineral buildup are evident or when the panel appears to be deteriorating. Scale and mineral buildup will occur faster if the water supply to the humidifier contains hard water.

 When replacing the water panel, remove the distribution and collection trays and remove any scale and mineral buildup by gently brushing or scraping. Stubborn deposits can be removed by soaking in vinegar or lime removing products.  For the best efficiency, install the panel with the spot at the top and make sure the distribution tray is level and evenly dispersing water over the entire panel.  Also inspect the orifice – a metering device that regulates the amount of water flowing to the distribution tray. It can become blocked with scale, which can be removed using a fine needle.

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Maintenance Kits
If a humidifier unit hasn’t been cleaned or inspected in several years, consider purchasing a maintenance kit, which will include the parts that are likely in need of repair, such as water panels, a feed-tube assembly, scale control insert, water distribution tray and a drain spud.

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When the weather warms up and the furnace is no longer needed make sure that the damper in bypass humidifiers is set to the Summer (closed) position. And always consult your product manual for specific instructions on how to clean your model.