Question about Emerson HDC12 Humidifier

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Left Tank won't empty

I just bought an Emerson HDC12 recently. I have made sure the unit is level front to back and left to right. I have filled both tanks with water and run it successfully until the F light lites up telling me to refill my humidifier. However the left tank stays full and never loses any water at all. I have switched the plungers between the tanks, I noticed the post for the left plunger is much lower so I stuck a spacer on the bottom of the plunger to offset the difference between the tanks, and lastly I am now trying the empty humidifier position. (Tying the float up stuck in the on position.) I won't know if this works until that right tank empties again. I can let water out of the left tank if I push up on the plunger so it is not geetting stuck in there by vacumn (I think). This unit is supposed to drain the right tank before the left but I thought they both were supposed to drain before the float fell enough to shut off the humidifier. Anybody have any ideas on what to try next? Thanks

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Re: Left Tank won't empty

Eureka! Solved my "left bottle not emptying" problem. The problem was not with the bottle but that the top of unit which houses the on/off switch was not seated properly. It takes only a very slight difference in water level for the float to activate the switch, therefore if the top is raised even 1/4" the unit will shut off before the water level is low enough to allow the left bottle to drain.

Posted on Jan 20, 2009

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Re: Left Tank won't empty

I had the same problem from day 1 with my MoistAir HD14070.
I inserted a piece of 4' square ceramic tile under each front wheel. This raised the front slightly more (unit is setting on carpeted floor) and gave the unit a more firm base to sit on. Works like a charm now.
Hope this helps someone.

Posted on Jan 05, 2010

Re: Left Tank won't empty

I've had the same problem. My solution has been to remove the plunger on the left tank. (Kind of defeats the purpose of changing the tanks without spilling water all over the place.) I really like the humidifier and this problem is minor compared with other humidifiers I've had in the past.

Posted on Mar 19, 2008

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Need owner's manual

You can try contacting Emerson to obtain the manual

Oct 19, 2013 | Emerson HDC12 Humidifier

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I had left my vicks vaporizer with water in it for like a month or longer and barely cleaned it out and now it doesnt work no steam or nothing will come out wats wrong is it broken???

The problem is more than likely due to a calcium and mineral build up in the tank and the tubing.
Hopefully, it's not to late to do something about it. So follow the instructions below,

Unplug the unit.

Remove any remaining water from the tank.

Mix a 50/50 solution of White Distilled Vinegar and Bottled Distilled Water (enough to fill the tank) and pour the solution into the tank. Allow t to sit overnight. In the morning, plug the unit in and turn it ON. If it doesn't start producing steam, turn the unit OFF, unplug it and empty the tank. Mix more solution as described above, pour it in the tank and allow it to set for 3 or more hours. The plug the unit in and turn it ON. Hopefully, this time, it will start to produce steam. If it does allow it to run until the tank is half empty. Turn the unit OFf and empty the remaining solution from the tank. Refill the the tank with Bottled Distilled Water and run the unit until it's empty. That will flush the system.

In the future, I would highly recommend the use of Bottled Distilled Water, rather than using tap water.

If the above didn't solve the problem, it's time to buy a new humidifier and use Bottled Distilled Water in it.

Jul 19, 2011 | Vicks Humidifiers

1 Answer


The unit may simply has a calcium scale build up and it's blocking the water passage. To clean it, empty in water remaining in the tank. Mix a 50/50 solution of White Vinegar and Bottled Distilled Water and fill the tank. Allow it to soak for at least one hour, then turn the unit ON. Place you hand in front of the misting nozzle to see if it's working. If you don't feel any mist, turn the unit OFF and allow it sit over night. If you do feel mist, allow it to run until the tank is 3/4's empty Turn the unit OFF, pour out the remaining solution and refill with Bottled Distilled Water. Run the humidifier until it's empty. This will flush the system entirely. In the future, I would recommend you use Bottled Distilled Water, instead of Tap Water. If you do, you won't have to descale the unit any more.

Hope this helped you, please let me know. Thanks.

May 16, 2011 | Vicks Warm Steam Vaporizer 1.5 Gallon...

1 Answer

I turn the humidifier on l or ll. The light is grean but it is not releasing steam or anything. I don't hear a noise and the water level stays the same.

The humidifier may be clogged with a calcium scale build up. Especially, if you use well water or your municipal water supply has a high chemical content.

To solve this problem do the following. Mix a 50/50 solution of White Vinegar and Bottled Distilled Water (enough to fill the tank). Empty any water that is currently in the tank and fill it with the 50/50 solution. Allow at least one hour, before turning the unit ON. After turning it ON place you hand in front of the mist nozzle to see if any mist is being generated. If it's generating mist, allow it to run until the tank is 3/4's empty. Then turn the unit OFF, unplug it and empty the remaining solution. Refill with Bottled Distilled Water and run until the tank is empty.

If the unit did not produce mist after one hour of soaking, allow it to set over night and then follow the procedure above. Generally, an overnight soaking will do the trick. In the future, I recommend using Bottle Distilled Water rather than your tap water.

Hope this helps you solve the problem. Please let me know. Thanks.

May 16, 2011 | Vicks Warm Mist V745A 1 Gallon Humidifier

1 Answer

Left bottle will not empty before the F button comes on what should i do

If the unit is on carpet, use the caster feet supplied with the unit. The weight of the bottles causes the front of the unit to be lower than the back. This prevents the sensor from switching bottles, causing the left bottle not to empty. The caster feet keep the water sufficiently level for the sensor to work.

Here is another thread on the matter.

Dec 20, 2010 | Essick Air 447 302 Console Whole House...

1 Answer

I have lost my manual. readout on the digital display is CF. humidifier operates fine. what does the display CF mean?

It means Change Filter.

However, assuming that you have done that in the recent past, you probably want to know more. I'm not sure how this actually works (that is why it shows CF). I saw it for the first time after 2 or 3 years of using my humidifier. (And I had just changed the filter a week or so previously).

You may have to turn the unit off/on or even unplug it to clear the message, then it should operate normally.

Nov 05, 2010 | Emerson HDC12 Humidifier

1 Answer

Sunbeam Ultrasonic Humidifier, model: 697-6

Located My Manual:
Hope this helps!

1. Remove tank from base. Turn upside down and unscrew filling cap. Fill tank with clean, cool, distilled, or tap water. Water temp should NEVER be too hot or too cold. Return tank to base and let sit for a few minutes. Be sure the filling cap of the tank is tightened firmly.

2. Plug power cord into a 110-120V AC wall outlet only. Turn power switch to "on" position. Power light will illuminate. Turn mist nozzle until desired level is being released. Aim nozzle away from furniture and walls.

3. Always turn humidifier off when water runs* out. Unit will continue to operate when tank is empty.
*Humidifier will run up to 12 hrs on low; 6 hrs on high.

Place unit on level surface away from direct sunlight.

Mild bleach and water solution for cleaning, never detergent.
Clean every 3rd day during use. Clean after long storage
Humidity varies from room to room. Aim for 30 - 50% relative humidity. If windows/ walls fog or frost, reduce mist intensity. If room too humid, ventilate by opening door or window; adjust mist intensity.

Sep 22, 2008 | Sunbeam Ultrasonic Humidifier

4 Answers


Try to just fill the tank with water and set it upright on a table. If it leaks, the tank is cracked and needs to be replaced. Order one at (search using model#). I have had this tank leak if the special cap is not sitting properly on the base. Make sure that the steam tower is properly locked in place before you place the water tank in the reservoir. The cap on the tank has a spring release that has to be correctly lined up so it only releases water when the water level in the reservoir drops.

May 08, 2008 | Vicks Warm Mist V745A 1 Gallon Humidifier

5 Answers

Kenmore 14-gallon humidifier--only right bottle will drain

I just read the reviews because I am considering buying it, and many owners complained of the same problem. Many people said they tried to fix the problems by leveling the machine, however, one guy said he figured it out: just level the machine slightly toward the REAR and it drains correctly. Try it. I hope he's right, because I'm going to take a chance on this machine and it better work well!!! :)

Mar 27, 2008 | Humidifiers

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