Humidifiers and Dehumidifiers - Aprilaire 700 Outdoor probe wire

I just received my Aprilaire 700 and I plan on installing it this weekend. A couple questions:

The outdoor probe has about 6' of wire. I will need to run about 20' of additional wire to get it outside. Any gage recommendations?

I can probably install on either the supply or return, but the supply would make it stick out into the walkway. Is there any real benefit over one way or the other (hot and cold water lines run right next to furnace)

Does anyone actually have a 120V plug near enough to the furnace to not run an extension cord? What are your opinions on converting the power switch at the furnace to a switch and outlet?

Thanks!
Bill

You can use 18 gauge 2wire t-stat wire for the sensor.

I'd go on hot water.

This model is best on the supply side since the hot air does a better job adding humidity into the warm air. It could work on the return, but be using a lot more water, longer run time.

As for power, let us know what brand of furnace and model you got.

Id also put it on the supply with hot water. Yes you can feed a plug in there by the kill switch for the furnace. For the humidifier 110V. Id put the manual mode control on the unit. Works a lot better . I think I had to change the R/H setting 2 times this winter is all

Thanks Ed and Jay. I will revist supply side.

Furnace is a Bryant 340MAV installed ~ 3 years ago.

One other question:

The furnace has 24 VAC terminals. Am I connecting the COM and HUM on the circuit board to the R and C terminals on the controller? I would assume so, but want to verify.

Thanks again! Looking forward to less static, not including the wife!

That's right about the wire hook up to control.

Much appreciated!

I will take pics to help out others if they need it.

I have been trying for two weeks to get my April aire 700 working I have a carrier furnace and have a hum and com hook uo going to humidistat 24 volt terminals I then hooked up the two yellow wires to the h terminals on the humidistat and with the furnice in the heat mode blower running blower on 700 on I cant get the water valve to open. I have 24 volts ac going to humidstat but none coming out to actvate water valve

Do you get water if you put on the manual mode??

I have been trying for two weeks to get my April aire 700 working I have a carrier furnace and have a hum and com hook uo going to humidistat 24 volt terminals I then hooked up the two yellow wires to the h terminals on the humidistat and with the furnice in the heat mode blower running blower on 700 on I cant get the water valve to open. I have 24 volts ac going to humidstat but none coming out to actvate water valve

Mine is working perfect, however, I am a bit embarassed to admit the following:

I hooked up the power wiring then the solenoid wiring and shut the breaker and the power switch for the furnace. The controller had a red led light that came on and no solenoid power. I shut off the power switch and made sure my connections were good. Again, red light, no solenoid opening. I then walked around to the other side of the furncae and saw my outdoor probe wire hanging from the ceiling. Once I hooked this up it has been running perfectly. Like Ed mentioned, if you do not have the outdoor probe wired, put the resistor in and try manual.

Ed or Jay, I have pictures if you would like me to send them for future reference.

Thanks guys!

If you don't mind, I would like to see pics of how you wired the controller to the humidifier. I have 24V from the furnace to the controller, then I wired H & H to the two brown wires coming from the humidifier.

I get no fan or water when I try to test or run the humidifier. Its plugged in, the furnace is running and calling for heat, the green light on the controller is blinking in test mode, i hear the switch in the controller turn on then off one minute later. No fan, no water.

If I jump the two brown wires and plug in the humidifier it cranks up. If I run wires from the brown wires and then jump them together to test the wires, it cranks up.

I don't get it, what the hell am I doing wrong???

If you could send me some pics of how you wired the controller to the humidifier, i would appreciate it. Send them to bucpride29@hotmail.com

Thanks, Jeff