Trying to figure out how to turn on my return fan when the thermostat turns on. The basement zone is on a damper system with the main zone upstairs - controlled by a zone panel. I have my Nest thermostat wired into the zone panel (with a C wire) and it works just fine. We got a 24V-110V relay and wired from the Common wire of the damper on the zone panel into the relay. When the thermostat turns on, the relay clicks but no power is transferred. Contractor believes he has the relay wired correctly. He tried just bare wire coming out of the relay but still gets nothing. Any thoughts as to what we're doing wrong and how to make it work?