Humidifiers and Dehumidifiers - Trying to hardwire HE260A to furnace

I was hoping someone could help me with how to properly wire my HE260A humidifier to my furnace. The humidifier came with a plug in transformer and a sail switch but I would rather wire it directly to the furnace. the board on my furnace has a HUM output (spade connector) but I believe it's 120V. I bought a 120V to 24V transformer but I'm a bit confused on how to properly wire it.

First issue is that this transformer has the attachment on it to attach to the knock out hole on a junction box. The junction box in my furnace does not have any knockout holes. It's more of a cover than a box, All that is in there is the power wire connection to power the furnace and nothing else. After reading other posts on this board I was hoping to find some HUM wires in there but no such luck. Can this transformer be used without attaching it do a junction box? Kind of a silly question but I'm worried that attaching it to a junction box works as a ground or something. Although where/how else would I mount it!?

Second issue. Once I get the transformer figured out, it has two wires on the 120V side. I assume they are for hot and neutral. The hot would come from the HUM spade connection on the board but where do I get the neutral from? I know some furnaces have HUM-H and HUM-N but all I have is one single HUM.

I hope someone out there can help me. Thanks in advance.

Ithe board on my furnace has a HUM output (spade connector) but I believe it's 120V. I bought a 120V to 24V transformer
Make and model of the furnace?


First issue is that this transformer has the attachment on it to attach to the knock out hole on a junction box. The junction box in my furnace does not have any knockout holes.
have something on the side of the furnace itself?


The hot would come from the HUM spade connection on the board but where do I get the neutral from?
Any where on the board that has an open neutral spade.

Make and model of the furnace?

This may be a silly question, but where can I find out? The outside has a KeepRite logo, but I noticed that the board has Honeywell stamped on it. The manual says "90+ Single Stage Category IV Furnace, N9MP1 & N9MP2, *9MPD, * Denotes Brands (C, H, T). Fan Assisted, Direct Vent Gas Furnace"

have something on the side of the furnace itself?

Actually I have a junction box I can mount inside the furnace to mount the transformer to.

Any where on the board that has an open neutral spade.

There is a group of 4 Neutral spade connections and two are empty so I can just use one of those!?

One other question, I took a reading with my volt meter off of the HUM spade connection and started the furnace, but there was no reading. I took a reading off of the G screw that the thermostat wire is attached to just to make sure I was using the voltmeter correctly and it jumped to around 24 when the furnace started. When is the HUM connection supposed to activate?

Thanks for your help.

This may be a silly question, but where can I find out?
Most of the time there is a sticker on the side in the burner area.

There is a group of 4 Neutral spade connections and two are empty so I can just use one of those!?
Yep.


One other question, I took a reading with my volt meter off of the HUM spade connection and started the furnace, but there was no reading.
Are you reading between HUM and Neutral spade?

When is the HUM connection supposed to activate?
When the burners are running.