In-Duct booster fan power source question

I have a room on the outside of the main house that has two in-duct booster fans to get a little more air in there. The contractor hooked each of these fans up to a always on AC source. So they were running 24x7 since being wired in about 5-6 years ago. They are now both dead - presumably burned out.

I purchased two replacement fans. Before I install them I need to provide a switched power source so that they are only running when the furnace is running - which I am hoping will greatly extend their life.

I have a Comfortmaker Model C8MPN100F14B1. I read in other posts that I could hook a relay to the EAC connector and have it trigger the fans. I looked on the circuit board of the system and I see markings for EAC but it looks like there is no connector. I do see what looks like a relay on the board next to it that has NO and NC connections that are open. Please see pictures attached.

If this does not work then I am guessing that I can install a duct stat and have that trigger the fans?

Any help would be appreciated. Thanks.