Question about Honeywell Warm Mist HWM-255 Humidifier

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Control panel After i turn on unit and set desired humidity level it flashes 90% as the current humidity level which is impossible. Have tried turnng off and on and still does the same.

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We just bought an idylis ultrasonic humidifier, but the directions don't make sense. It says to push the button in and wait til it pops out to set the humidity level. It nevers pops out by itself.

I am very fond of my Idylis humidifiers. Best I've ever had. When I bought a 2nd one, I noticed that the HUMIDITY SETTING button had a small sticker on it that said "PUSH TO ROTATE". My larger unit [no longer available] did not have the sticker. And, the sticker instructions are indeed confusing. The button actually has 2 positions 1) when depressed all the way in the settings are locked in place and 2) when pressed in just enough to pop the button up and outward, the button becomes a rotating column that can be turned either L or R to set the desired % humidity. Once the digital readout is at your preference, push the column/button in to lock it down and secure your setting. OMG, so wordy on my part! I think the darn "PUSH TO ROTATE" sticker is not helpful.

Jan 27, 2013 | Humidifiers

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These hints are from the air o swiss webpage.
Q: No mist / unit is not working / empty indicator keeps flashing
A: Fill up the water tank. Check if water is flowing through the demineralization cartridge (attached to the water tank cap). If the water tank is full but there is only little water in the base it indicates that the water is now flowing through the demineralization cartridge.

  • Wait for 15 minutes to allow the mist to come out of the unit.
  • If the unit is not working and the empty light is not flashing you might have set the desired humidity too low and the current humidity level in the room is higher. That is why the unit switches off automatically.
  • If the empty indicator continues flashing and the tank is full, water is not flowing through the cartridge. Exchange the cartridge or the granules in the cartridge after 2-3 months, in areas with hard water exchange the cartridge after 1 -2 months. However, the demineralization cartridge and or the granules must be exchanged at the latest after 6 months or the unit does not reach its full performance.
If the granules are new, see the following instructions:

  • Make sure the cartridge and/or granules were soaked for 24 hours, water takes longer to filter through dry granules in cartridge and into the base. Next, remove 2 tablespoons of granules from the cartridge, and throw them away. Too many granules in the cartridge it does not allow water to flow from the tank to the base.
If your issue is with the float and not the mister, then you have to make sure the float is tripping the micro switch that turns the machine on. Some units the filter will not allow the float to hit the switch if the filter is not installed correctly. If everything is in correctly and the float is tripping the switch, then the micro switch must be faulty.

Apr 04, 2011 | Swiss AIR-O-SWISS Ultrasonic Humidifier -...

1 Answer

After cleaning everything the humidifier no longer runs. When I turn it on no matter what level I set the desired humidity to the green light goes on indicating that it is at the desired humidity. Before...

The humidstat controler has failed. By cleaning the humidfier you introduced moisture into the system. Dry the humidstat controler with a hair dryer and try the humifier again. If the unit still does not shut off at maxium setting. Replace the humidfier controler.

Jan 26, 2011 | Hunter 32300 Humidifier

1 Answer

The humidifier says "desired humidity" when turned

I would say, either the humidity level in the room is hi or the humidifier is defective, In my house the humidity is about 42% to 45% when we use the humidifier, and can drop to 30% or less if we don't, we leave in DC area,
I hope this helps.

Jan 14, 2011 | Vicks V4500 1 Gallon Humidifier

1 Answer

I have an old Aprilaire 550. Can't get the humidity to desired level of 40-45% humidity, only 36-39%. Is there anything I can do. Water is very hard in my home could this be the reason why water isn't...

Sorry to read about your problem, I hope this helps you out.
You are at the limit of what the unit can do.
One little thing you can do is see if the unit is hooked up to hot water instead of cold water.

-20F -29C 15%
-10F -23C 20%
0F -18C 25%
+10F -29C 30%
+20F - 7C 35%
+30F - 1C 40%

I tried to help you. Please help me and Rate/Vote on my response, thanks and good luck

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Dec 26, 2010 | Aprilaire 550 Humidifier

1 Answer

Not working

HI, Troubleshooting an Aprilaire Humidifier

Aprilaire, a manufacturer of indoor air quality products including thermostats, air cleaners and dehumidifiers, also offers a line of whole house humidifiers. Installed in your existing heating and cooling system, humidity is produced by a supplied water source that flows over a water panel before being distributed throughout your air through the heating and cooling system. Issues you may need to troubleshoot with your Aprilaire humidifier include error messages and the unit producing too little or too much humidity.

Things You'll Need:

Replacement water panel

Turn down the control dial by one setting if condensation appears on your windows or walls.

Turn up the control dial by one setting if there is a lack of humidity, often indicated by dry skin or peeling wallpaper or paint.

Turn the control dial to "Test/Reset" if the humidifier does not run. Verify the heating and air conditioning unit blower is operating. If the heating and air conditioning unit is not operating or you are unable to resolve the issue contact a heating contractor.

Contact a heating contractor if you turn the control dial to "Off" and the humidifier continues to run.

Contact your Aprilaire dealer (see Resources) if you notice an error code on the display and the "Call Dealer for Service" light flashes.

Turn the control dial to "Off" and turn off the water supply if the yellow "Change Water Panel" light flashes. Lift the front panel off of the humidifier. Slide out the water panel. Insert a new water panel. Replace the front cover. Turn the control dial to "Test/Reset" until the "Humidifier On" light flashes. If you feel uncomfortable changing the water panel, contact a heating contractor.

Tips & Warnings

Purchase replacement water panels through your Aprilaire dealer or a heating contractor.

You can get parts from the link below:

Hope it helps.

Thanks for using fixya....

Nov 17, 2010 | Aprilaire 700 Humidifier

1 Answer

760 aprilaire humidifier does not let water to the filter. I have cleaned and checked the lines in and out of solenoid.

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  1. No click at the solenoid valve indicates an electrical problem. Contact your heating and air conditioning dealer to further check the electrical components of your Aprilaire Humidifier.

  1. The click sound at the solenoid valve indicates there is electricity to the solenoid valve. By turning the dial of your humidifier control to a setting above the “click point” you should see water coming out of the drain line within a few minutes which would indicate your humidifier is working.

  1. If the solenoid valve makes a click sound and there is no water draining from the unit, this would indicate the flow of water is being obstructed.

1. To determine if water flow is being obstructed, turn the dial of your humidifier control to the off position. The first location you would want to check for an obstruction would be at the saddle valve located on the water line supplying water to the humidifier. When checking the saddle valve, you want to make sure it is completely open. This can be done by turning the valve all the way to the left. If anything is clogged, it can be dislodged by turning the saddle valve all the way to the right and back to the left. Once this is done, turn the humidifier control dial above the click point and you should see water coming out the drain line.

If water is still not coming out of the drain, check the orifice and in-line strainer to make sure they are not clogged. The orifice is located in the tube on the discharge side of the solenoid valve and the in-line strainer is located on the inlet side of the solenoid valve. You may clear the orifice by inserting a needle through the small opening. Clean the strainer by running it under warm water to dislodge deposits or replace. After clearing and re-installing the orifice and strainer (be sure to double wrench all water connections), turn the humidifier control dial above the click point and you should see water coming out the drain line.

Mar 10, 2010 | Aprilaire Humidifiers

1 Answer

No matter what setting is put on furnace humidifier, moisture forms on windows.House is only 6 years old and does have a lot of windows.

Hello WPwilkers, Well there's good news and good news!

First off, you should probably use the lowest possible setting as your house being so new, is likely pretty "air-tight" and as such, doesn't have a lot of air infiltration (gaps and drafts) hence the reason you're seeing moisture on the windows.

Now, I would also use a hygrometer, just like your parents likely had hanging on a wall somewhere in their house. It will give you a better idea of the moistur (humidity) around the house. My guess is that you're already at the 60%+ level of humidity.

I suggest that you turn "OFF" the furnace mounted humidifier, until you no longer see moisture on the windows. That will allow the house to adjust and get back to normal humidity levels.

Then you can start by setting the humidifier on the lowest possible setting and keep an eye on the moisture levels in your coldest room of the house, as that is where you'll first notice the excessive moisture on the windows (just the way it works - cold rooms get condensation on the cooler windows first).

If you don't have the humistat (the control for the furnance mounted humidifer) mounted next to your heating and cooling system thermostat, you should do that - it will make it easier to adjust and also will provide a more accurate reading for the humifier to operate properly.

Some Thermostats have the ability to add a humidifier on it for integrated controlling of the furnace humidifer. Check your Thermostat and Furnance owner's manual for details.

I used to have the same problem and found that by moving the humidifer control from the utility room (mine was in the basement of my house) to the living space, it made a big difference. Since most people's homes have unfinished basements and that's where the HVAC system is located, it doesn't get the same humidty readings as an occupied living space.

The other reason that you tend to get moisture (condensation) forming on windows is that the Percentage of humiditfication is set manually with the humidifier control, and yet, the outside (and inside) air temperature vary and the difference between them can cause the humidity levels to go from very dry to very moist, in a day or two.

I tend to wait until I notice that the air inside the house is getting dry and then turn on my humidifier, once the cold winter days have taken hold. In summary, nothing wrong with your unit, just mother nature and a well built (most air-tight) home are giving you higher levels of condensation than most older homes. Gradual adjustments, once you turn the humidifier off for awhile, should get you the desired results.

I hope you find this Very Helpful and best regards!

Dec 17, 2009 | Honeywell HE365 Humidifier

2 Answers

Aprilaire 600 humidifier solonoid valve chattering in sync with d10 led

I fixed my problem by ordering a new control unit (model 56) from IAQSOURCE. Installing the control unit took a few mintues, and once the new control module was installed, I've had no more problems. The URL is as follows:

Oct 12, 2007 | Aprilaire 600 Humidifier

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