I have an Aprilaire 700 brand new install with a Goodman High Efficiency Unit. I have not been able to get the Humidifier to work and I can't get it to work in test mode. At the humidifier control board, The R anc C connectors go to a 24v transformer, where I get a 24v reading at the humidifier. The ODT is on Manual Setting with the manual insert tab, The W is connected to the blower pressure switch and the C is connected to the C on the 24v section of the Goodman Controller board. Both test to 24v at the humidifier control board when the blower is on and the unit is calling for heat. The H and Gf outputs on the humidifier controller board are connected to the brown wires coming out of the actual humidifier. I do not get any voltage reading at the humidifer controller board when Goodman Unit is on and the furnace is working. Can you please help? I have tried replacing the relay in the unit as well as the solenoid and it still does not work.

the float may be bad or sticking allowing water to run continusly even when unit is off.

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

Make sure the fan unit door (over the water panel) is closed. Push on it to ensure it is fully shut.

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

There is a small oriface that is installed next to the solenoid valve. It sounds like this oriface is missing. It reduces the water flow through the humidifier when it is working properly. You should be able to disassemble the solenoid fittings to check and see if the oriface is in the water line. For a "temporary" fix regulate the water pressure down by closing down on the saddle valve.
Good luck
HVAC Teacher

You may be having problem with air scaping from the base of the hum. it will probably may have to put silicone around the base of the hum. to stop the air scaping.

turn the humidistat back up, aand make sure if is still wired up.

check this website for a wiring diaghram Aprilaire 700 Repair Parts & Supplies
http://www.arnoldservice.com/Aprilaire_700_repair_parts_supplies.htm

I called the service company that put in my new furnace (FAmily Heating and Cooling in Detroit, very highly recommend these people)

Anyway they sent out a second service tech who determined that I would be better off having the humidifier wired to go on whenever the furnace fan was running instead of using the humidifier signal from the circuit board on the furnace. After he changed the wiring the unit runs fine. It is pretty likely that the circuit board was bad also.