Humidifiers and Dehumidifiers - Wiring Aprilaire 600a to Trane XR80

Hi all,

First of all, thanks to this forum I have installed my first humidifier (I've been lurking the last two weeks).

I've installed my humidifier (600a) to my Trane XR80. My only issue is the wiring, I'm lost.

My first crack at wiring was

Humidistat -> Furnace
R -> 24V Transformer (hooked to HUM-H)
C -> 24v Transformer (hooked to HUM-N)

W/G -> G
Cf -> C

This "worked", but only when the heat was called for, the humidistat wasn't receiving a constant 24V. So, I swapped the to the following setup

Humidistat -> Furnace
R -> R
C -> C

W/G -> 24V Transformer (HUM-H)
Cf -> 24V Transformer (HUM-N)

That got my constant 24V working so the control panel was always lit, but the water valve won't kick open in test mode without the furnace on...is this okay?

Any help would be appreciated, and again big thanks to the forum.

That is correct, you will get power on HUM when the furnace fires off.

Did you mount the transformer like I've done on mine? (if you saw the photo)

Perfect, thanks.:)

I didn't know how to mount the transformer as it didn't come with an end that would mount on an electrical box knockout.
http://www.iaqsource.com/product.php?p=aprilaire_4010&product=110975 (http://http://www.iaqsource.com/product.php?p=aprilaire_4010&product=110975) (for reference)

It is currently "mounted" with 2 plastic cable ties to the metal box that holds the control board. I couldn't think of any other way to mount it.

Is there a better way?

I didn't know how to mount the transformer as it didn't come with an end that would mount on an electrical box knockout.
it has an end on that you can mount the transformer.. The screw on back of it secures it to the knock out.

Here is how mine is done.
http://img522.imageshack.us/img522/5061/imgp0383up4.jpg

Thanks Jay, I'll take a look again.