How to check if your humidifier is working

First we recommend that if you have a drum style humidifier or an L-40 humidifier (similar to pictures 1 & 2 below) that they be replaced with a bypass humidifier (picture 3). These are older less effective models that are not going to be economical to repair.

Here’s how to check if your humidifier is working:
  1. Ensure your humidistat is turned up to the highest setting. Turn your furnace thermostat to heat and turn up to call for heat on the furnace. Typically, humidifiers only work in the heating cycle.
  2. Ensure your water line to your humidifier is turned on.
  3. Lift the supply tube to your humidifier from the top of the distribution box slightly, can you see water coming out of it?
  4. If yes, ensure you have your season selector dial on the appropriate season, especially if you have air conditioning in your home. Skip to step 7.
  5. If no, check for 24 volts AC at your solenoid valve (shown in picture 4 below). If you have between 24-28 volts present, and water is not coming out of your solenoid valve, then valve has failed and must be replaced.
  6. If you do not have voltage present, we would recommend you contact us for assistance, this could be a wiring issue in your furnace or humidistat (shown in picture 5 below) that should be looked at by trained professionals.
  7. Check you have water going through to your drain hose, most likely its running to your floor drain.
  8. Have you changed your humidifier pad this year? It should be changed annually. Simply turn down your humidistat, then undo both screws on either side of distribution box. Lift out old pad and insert new pad.

We hope this information can help you determine whether or not your humidifier is working correctly and efficiently in your home. Please feel free to contact us with any questions or concerns. We would LOVE to help you out.