Last year I installed an Aprilaire 600 humidifier on my 30 yr old oil/hotair furnace. Smacked myself for not doing it 20 yrs ago- It didn't cost much more than one of the dozen or so portable humidifiers I futzed with over those years. It did a better job of humidifying- and was no work at all.
Thanks to whoever asked about one on this group- or I probably never would have woke up.
But then I saw a great deal on a new furnace on Craigs list- and just got done installing it. I just ran it through one cycle to test for noise & leaks. The HVAC guy comes Friday to check my work & tune it up.
On the old furnace I wired a transformer to the fan so when it kicked on, the solenoid kicked on the humidifier. For the life of me I can't remember how I did that now. The schematic in the [furnace's] installation booklet don't make sense to me.
Could someone look at these and try to put into words where the transformer wires-- 2 black & a green-- go? Schematic