Your serial number is on the sticker on the back of your fan assembly.

We recommend an indoor relative humidity level of 40-60%. This range is best for creating a comfortable environment, and it is at this level that cold, flu, and other viruses tend to fall apart.

For single room humidifiers, place the unit in the room where humidity is most needed. Whole house humidifiers should be placed in the most centrally-located room of your house. Putting your humidifier next to a cold air return will help spread humidity throughout your home more quickly. Whole house humidifiers should be placed on the bottom floor of multi-level homes.

This depends on the unit. Single room humidifiers can bring the humidity up in a room relatively quickly. Whole house humidifiers typically need 2-3 days to bring your humidity up, especially if it is very dry in your home.

Yes, you can buy most replacement parts individually. Refer to the owner’s manual that was included with your Horizon, or click here, for a complete list of replaceable parts.

Your first ­­­HDC411 wicking filter set is included with the purchase of your humidifier.

You should replace your filter every 60-90 days. Keep in mind that your water may allow for less frequent replacements, or require more frequent replacements. Everyone's water is different and contains different minerals that will affect the life of the wicking filter.

No, the wicking filter is made with a special absorbent paper that will fall apart if you try to wash it.

You can buy replacement humidifier filters here on our site, from our retailers, or by calling us at 800-547-3888.

Your humidifier will operate only when all components are correctly installed. Make sure your wicking filter and float rod are both correctly installed. Check your owner's manual included with your humidifier, or the online version here on our website.

This alert triggers to let you know your humidity level is below 20%, which is too low. Try increasing your fan speed and output level.

This alert triggers to let you know your humidity level is over 90%, which is too high. Try lowering your fan speed and output level.

The “CF” code triggers after 720 hours of use and means it’s time to CHECK your filter. If your filter is still in good shape, simply clear the code by unplugging your unit then plugging it back in. If your filter needs replacing, let your unit dry completely, then replace your filter with a new HDC411 Super Wick®.

The “F” code means your unit is empty and needs to be FILLED.

Try adjusting your float.

Your CONTROLS ARE LOCKED on the current setting. Activate the control lock by holding the power button for five seconds, until CL appears. Your Horizon will lock on the current fan and humidity settings. Release the lock by pressing the power button again for five seconds until the display flashes “CL” three times, letting you know the lock is off.

The mist is not visible. Evaporative humidifiers use a wick to absorb water. As this absorbed water evaporates, a fan blows the evaporated water vapor into your home to humidify your air.

No, essential oils will damage this humidifier. You CAN use essential oils with our ultrasonic humidifier models.

The Horizon is a pour-in humidifier. To fill it, you lift the pivot lid, and pour water directly into the unit.