I have read most of the posts here and have a specific question about my install. In the picture you can see the 3 blue wires coming off the 24v side of the transformer. One goes to the side and than another blue wire is connected to the metal and goes to the ac unit outside. One goes up to what I believe is the exhaust fan. The last one connects to the circuit board. There is also a 24v HUM screw on the board. My question is should I connect to the 24v Terminal on the board or one of the wires that are screwed into the metal next to the transformer. Thanks for any help.