Recommended Annual Maintenance
The water panel should be changed once a year, with a few exceptions.
- The model 400 has a panel that should be changed twice a season
- If extremely hard water is used in any Aprilaire humidifier, the panel should be changed more frequently than once a season.
- The water panel cannot be cleaned because it has a special coating that helps the water adhere to the panel while the air is passing through it. Without the coating, more water will go down the drain and less will be converted into a vapor.
- Detach the drain line from the drain spud at the bottom of the unit.
- Bend it at the various points to loosen calcium deposits which may have formed on the inside of the line, and flush it with pressurized water.
- You can also pour bleach through it prior to the water. This will kill any micro-organisms that happen to be living in the drain line.
- The drain line can be replaced should it prove difficult to clean.
- Detach the tube from the nozzle at the top of the unit, and unscrew the end of the solenoid valve at the other end of the feed tube.
- Run high pressure water through the tube and replace.
- When reconnecting the feed tube, remember to double wrench the connections to prevent leaking.
Inside of unit
- Look for any mineral deposits on the Scale Control Insert after removing the water panel, and get rid of them by wiping the insert with a damp towel or rag. They should come right off.
- If there are deposits on the inside of the cover, or in the case of a 700, on the fan blade, it may be indicative of a larger problem known as entrainment. ()
Do not remove granulated coating on the distribution tray – not an issue with the new ones.
- The granular coating is there to break up the surface tension of the water. This allows water to flow evenly through all of the openings in the water distribution tray.
- The newer trays have a fabric along the bottom of the tray which does the same thing as the granular coating. The difference is the customer doesn’t have to worry about scraping off the fabric.
Hard or Soft Water
- Aprilaire offers total flexibility in the installation of our humidifiers in that they will operate properly with either hard or soft water. Connecting to hard water may leave mineral deposits on the water panel that are scaly and hard in nature. Connecting to soft water may leave mineral deposits that are fluffier in nature. The bottom line is the water panel will typically last a full heating season using either type of water. When extremely hard water is used in the humidifier, maintenance should be performed approximately every six months.