My unit is about 6 months old. One night we heard this terrible metallic vibration from the furnace unit. I tried several times to locate it but it would stop by the time I got down in the basement to find it. Finally I happened to be down there when it happened. It was the humidifier water inlet valve. When it kicked on it was vibrating against the duct making the noise. I disconnected it and I am looking for parts now..... Just another possibility.
A noisy humidifier may be the result of an unlubricated fan motor or a drive mechanism clogged by debris. Periodically clean the water reservoir, fan, and nozzle to ensure that they are clean and working properly. To keep your humidifier working smoothly and efficiently, lubricate the fan motor bearings with SAE #20 oil. Be sure to consult your owner?s manual for proper care and maintenance procedures. If it seems loose, vibrating parts are causing the noise: 1) Disconnect the power. 2) Remove the cover and look for any vibrating parts. Tighten screws, if necessary. 3) Wiggle the fan to see if it is loose on its shaft. If it is, tighten the mounting fasteners. Lubricate the motor's bearings if suggested in your owner's manual. 4) If it still makes noise, call an appliance repairperson or take the unit into an appliance repair shop.
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