Help wiring humidistat Rheem v96

[rhconcepts]

Need help wiring this Trion mister in to the furnace. I have a ecobee 3 lite so I have to use the included humidistat. My furnace guy is out fishing but told me to use the 2 HUM terminals. But when I check for voltage I never get 24v when the heat kicks in. What he told me is not what the manual shows. The problem with the manual is it shows a external power and relay. How can I use the 24v off the furnace.
Do I need to use the R, C and HUM STAT and can I get 24v from the board?

[rhconcepts]

https://www.hvactechgroup.com/hvacforum/index.php?topic=2527.msg8178#msg8178

Just found this. What the Admin wrote makes sense so Im going to try it. But I want to know will the board give enough power for this mister?

OK its working but im getting power coming out when I turn just the fan on. I think that's ok because the mister won't spray until it senses a high temp going over it. But how can I make my fan run a bit longer after the heat turns off? If the fan ran a bit longer it would dry the duct where the mister is installed.