Why is water leaking at bottom when turned off?

Bionaire BWM401 leaking - YouTube

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https://www.youtube.com/watch?v=Gy7VKJJeb3o
Jan 20, 2013 - Uploaded by urhorh
My Bionaire BWM401 leaking through the bottom. ... Review ofBionaire Cool Mist Humidifier BCM7932P-CN from Costco HD - Duration: 1:41.

Hi they should be a hose going to a drain in the floor there are insrtuctions on the wed just google the make and model and you can down load them

Install new water panels yearly. On the new panel make sure that the painted dot on the edge of the panel is on the top when you install it.
Always clean the distribution tray and the frame. Make sure the notch on the edge of the distribution tray faces away from the furnace. Make sure the humidifier was installed level. Keep the drain tube opening clear. Insure there is no blockages in the drain tube.
Good luck
HVAC Teacher

Check your plastic water orifice. It is in the hose fitting connected to the outlet tube of the water solenoid. It should be a blue one. Mine was completely eaten through, allowing full water flow, and thus overflowing the distribution tray. I replaced mine yesterday and no more water drips. May as well reflace the filter on the inlet tube of the solenoid at the same time. I used a piece of very stiff, but thin, wire formed into a small hook to remove both old parts. Replacements are readily available from multiple sources on line.

The tune up kit that I ordered arrived on Friday and I installed most of it on Friday night. While it is nice to have a new frame and the distribution panel and I think the price of the whole kit was fair considering it comes with the parts and 2 water panels, the fix was really simple.

The kit came with the water distribution tube with with a new blue orifice (Aprilaire #4232) already inserted. This orifice is in the end of the plastic tube at the solenoid end. When I removed the old water distribution tube, the old orifice was not really dark blue anymore but kind of a light blue and was deteriorating from 12 years of exposure to the chemicals in the water. What should have been a pin-hole size opening in the orifice was up to about 2mm or a little more so the orifice was letting way too much water through.

If anyone else has this leaking problem, and your orifice is several years old, I would check that first. It is a $2.75 part and may be the cause of the leak. The whole feed tube kit is only $8.75 and includes the feed tube, nozzle, orifice, ferule, compression nut, strainer so if you need to replace the orifice, I would order the whole feed tube kit for a little bit more.

Hope this helps,
Roger...

Check the bottom of drain tube (tube connected to the bottom center of the bottom tray). Does water freely flow out the tube when the humdifier water feed is on?

If there is no flow from the tube and water is leaking from the bottom tray when the humidifier water feed is on then the tube or bottom tray is clogged with hardwater minerals or other material.

If the unit has not been used in a while it's possible a spider has take up residence by spinning a web in the bottom tray or tube.

The last poissible reason is the tray is cracked. You may order the tray from multiple sources on the web. Simply shop for model and price.

Check the bottom of the drain tube (tube connected to the bottom center of the bottom tray). Does water freely flow out the bottom end of the tube when the humdifier water feed is on?

If there is no flow from the tube and water is leaking from the bottom tray when the humidifier water feed is on then the tube or bottom tray may be clogged with hardwater minerals or other material.

Also, if the humidifier has not been used in a long while it's possible a spider has take up residence by spinning a web in the bottom tray or tube. Tell the spider to find a new home.

Another possible reason is the tray is cracked. You may order the tray from multiple sources on the web. Simply shop for model and price.

And lastly, is the unit installed properly, parallel to the ground? If tilted, water flowing through the unit may catch the sides and flow out where it should not.

A leaking humidifier is a sign that the unit's filter needs to be cleaned/changed. I had the exact same problem on this model.

There are a few hose connections inside the unit related to the heater element. Water flows from the reservoir down into the unit, takes a turn into a tube with the heater element wrapped around it, then turns back up into the mister area. Any of the four connections (base to first elbow, elbow to heater tube, heater tube to second elbow or second elbow to base) could be leaking.
The white ring around the mister disk cracked on my unit, letting water leak out the bottom as you describe... Take a close look at that.
It's also possible the base itself is cracked somewhere... Look closely at the mister and reservoir areas of the base for cracks.

Make sure the bottom port on the humidifier is seated properly in drain port. Make sure your drain line is not obstructed.