When the system calls for heat My Aprilaire 700 fan turns on, but the solenoid doesn't open up. The indoor humidity is around 35% now, outside temperature was around 35 with relative humidity of 75%. In the test position the fan turns on but agin the solenoid doesn't seem to be opening. Is it possible I have a blockage from mineral buildup. There is no errors being reported by the control panel. I checked the connections which seem to be fine. The sytem functioned fine last season, but is giving me the solenoid problem. I changed the water curtain filter as well.

Is this a newly installed unit it sounds as if there's a wiring issue. Could you show a picture of the wiring terminals. If this is not a new install try turning of your furnace fan.

Hello, the humidifier should turn on and off with the furnaces blower motor. Usually if it runs continously it means the solenoid valve is stuck open, in this case the solenoid valve must be replaced. The condensation is normal comming out of the pvc pipe, and the humidistat should be set according to your outside air temp

Outside Temperature -10 F 0 F 10 F 20 F 30 F Recommended Indoor
Relative Humidity 20% 25% 30% 35% 35%

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:

arnoldservice.com/humidifier_parts.htm


Hope it helps.

Thanks for using fixya....

It appears your Aprilaire model 700 is wired to only operate when your HVAC fan is operated by your thermostat. Your HVAC installer can wire the humidifier control to operate the humidifier during a heat call, fan call or to turn on the fan when there is a need for humidification. Please contact your HVAC installer to have them change the wiring.

Thank you for giving us the opportunity to be of service
Sincerely,

Brad Uselmann
Technical Support
Research Products Corporation
www.aprilaire.com

unless the humidty in your home is higher then 35%. if it is then the humidifier would not run. try turning it up higher and see if it comes on. Do you hear a click in the humidistat? as you turn up the dail when you hear the click is when the humidifier should come on. Also remember your furnace must be running for the humidifier to come on. if you hear the click and the humidifier fan comes on but no water, you may have a clogged inline filter located in the solinoid valve or a bad soliniod. all parts for your humifier can be purchased from www.aprilaire.com

if you mean your aprilaire humidifier isn't working then open the cover and remove the 4 screws on the fan motor mount inside and check for voltage at the transformer input 120 volts and output 25.5 volts a.c., then check the control board wherever you have it located on the furnace or upstairs and make sure yhe humidity level is set high enough to make the unit run(you will hear the water solenoid click on the furnace below the aprilaire unitwhere the water line is if its working correctly),then check the humidistat on the outside of the building as they can go bad

Thanks for your question,
Sounds to me like you have a bad solenoid valve in your Humidifier, this will need replaced, the solenoid is supposed to open and close when there is a call for humidity only when the furnace is running, then when the proper amount of humidity is sensed by the humidistat, then will it shut off, with the solenoid not working it will let water flow through like an open faucet, the solenoid is the componet that the 1/4in copper tubing connects to at the humidifier, has two wires running from it, you will need to shut the power off before changing this out, also shut the water off at the valve at the other end of the 1/4in copper line, or you might get soaked,please be careful when installing the new solenoid, making sure the water line connection is secure, or you will have leaks, hope this was helpful, please leave a rating, thanks again for your question,
mr.grzz

if it is set up right, you should be able to run your fan 100% of the time and the humidifier will come on when there is a need for humidity. you can experiment with leaving the fan on and see if this helps. it will run your electric bill up a little and also you will have a lot of waste water. that is a drawback to the bypass type humidifiers. also a factor is if the water supply is hooked up to the hot or cold side. it will humidify better on the hot side, but you tend to get more deposits that plug the solenoid over time and you will be running your water heater quite a bit. 1600 sqft may be pushing the limit of this humidifier.

You should take out that aprilaire and throw it in the garbage or return it to who you got it from. Ask them why they didn't offer you the best humidifiers available. The only way to truly control humidity in your home without running your heat is a steam humidifier. Autoflo makes a good one also honeywell makes a new one. I have installed a honeywell tru steam in my own home and a few customers it hasn't lived up to its advertising. The auto flo has never given me any problems with customers.

I have a similar problem with mine too. I am interested to see if anyone can diagnose this problem