I'm thinking of Nano temp controller from BBQ Guru, but the adapter they sell for the WSM is one size fits for both the 18" and 22.5". Anyone have any comments?
Don't think its a problem. I have the Nano and an 18". Use silver duct tape (real heating duct tape) to seal off two holes on one vent (close other two vents), then screw in the adaptor.
Shouldn't be an issue at all. The fan controller will control/adjust the volume of air and the fan itself has a slide/port that allows you to open/dampen overall air flow as well. I keep the slide half closed typically on the 18" WSM you may go full open for the larger WSM. Either way though the fan has plenty of capacity for either model WSM IMHO.
I've used my DigiQ 2 with a ProQ stacker added to my 18" and had no issues controlling temps with the added volume.
I used the mount through the vent with the tape as described for a couple of years with excellent results. Finally drilled a whole with a step drill about a year ago and it made it much more convenient as when not using the controller I have full use of the vents without having to remove the adapter.
