Whole house humidifier

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brasilmom

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Hi all,

Last year we installed a whole house humidifier as it gets way too dry during the winter. So, this year since we have been using the basement for often and it is being kept heated, the furnace is not running as much, and in consequence the humidifier is not either. The current humidity of the house is 30%, and the temperature outside is falling fast.

So, is there a way to have the humidifier running with the furnace fan only? We keep the fan running so the air circulate a bit, but that does not turn on the humidifier. Help please!!!

Thanks. Be well

Miriam
 
Yes, the solenoid for the water valve is only energized when in "Heat" mode.
You need to tap the fan circuit to energize the solenoid for the humidifier.
 
I see. So, is that something that is relatively easy to do? My husband checked the wiring, but we had had little time to work on it. Are you saying that the wiring shall be done through the fan rather than the "heat"? Pardon for my ignorance, and trust me I am not good with electricity.

Be well. Miriam
 
while this is technically electrical in nature it is only 24VAC and won't hurt you.
I'm not saying hook it up to the fan but, utilize the thermostat fan control circuit to energize the water solenoid for the humidifier.
If you could post some pics of the setup, I could provide you instructions on how to rewire. I would need to see where/how the humidifier circuit is wired. Sometimes the tap the heat circuit, sometimes they have their own transformer.
 
I am glad o hear I would not hurt myself. Certain things, one never knows.
Ok, so I took some pics and I hope I can post it so you can check it out. I hope you can understand the wires, if not let me know and I will try to help. Thanks for your help. Be well. Miriam

IMG_1743.JPG
IMG_1744.JPG
IMG_1745.JPG
IMG_1746.JPG
IMG_1747.JPG
IMG_1748.JPG
IMG_1749.JPG
 
Maybe that did not work for the photos. Let me try again. I hope this works. Thanks for your help. Be well. Miriam

IMG_1743.jpg

IMG_1745.jpg

IMG_1747.jpg

IMG_1749.jpg
 
Ok, I'm looking at a high-efficiency furnace with a built in humidifier and/or built in controls for a add on humidifier.
I need to see or you can post, the 7 terminal descriptions under the white thermostat wire in pic #2 (W, W1, Y1, Y2, G, R, HUM, etc...).
I also need to know where the red wire is connected (terminal designation). This is the red wire coming out of the white wire where the white goes to HUM.
 
Usually the humidifier is located on the plenum, over the furnace. These photos are of the inside of your furnace.
 
Yea, by built in I mean "a package deal" not an add on.
 
Ok, I'm looking at a high-efficiency furnace with a built in humidifier and/or built in controls for a add on humidifier.
I need to see or you can post, the 7 terminal descriptions under the white thermostat wire in pic #2 (W, W1, Y1, Y2, G, R, HUM, etc...).
I also need to know where the red wire is connected (terminal designation). This is the red wire coming out of the white wire where the white goes to HUM.
I cannot get a very good pic of it due to the wiring. However, here is the info:

W2, COM 24V (red connected to it), W/W1, Y/Y2, R, G, HUM

Hope this helps. Thanks for your help. Be well

Miriam
 
I cannot get a very good pic of it due to the wiring. However, here is the info:

W2, COM 24V (red connected to it), W/W1, Y/Y2, R, G, HUM

Hope this helps. Thanks for your help. Be well

Miriam
Oh, and the humidifier was added on. We do not know if the furnace came with one, however it seems like there was one. Again, unknown if it was built in or added on.

Thanks. Be well

Miriam
 
Move the white wire off the HUM terminal and place it with the green wire on the G terminal.
This should energize the humidifier solenoid whenever the fan comes on (even when in A/C mode) so you might want to undo this change for A/C.
Let me know how it goes.
 
Thank you. It is working now. So, the G terminal is for the fan? What does G stand for?

Again, thanks for helping out with this small issue.

Be well

Miriam
 
Yes, G is for the fan, G stands for Green.
Your very welcome, glad to help.
 
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