A fire damper for a ventilating fan includes a shutter and a frame provided with a flange. A preformed opening is provided on the frame. The frame is further provided with a movable component for opening or closing the preformed opening. This has the advantage of being able to share parts with others.

An electronic thermostat is described that includes a head unit, a rotatable ring, a backplate, an electronic display that is viewable by a user in front of the thermostat, a printed circuit board, and a daughter circuit. The daughter circuit is coupled to the printed circuit board, and senses motion of the rotatable ring and includes a first temperature sensor. A second temperature sensor separated from the first temperature sensor, are both used to calculate ambient temperature. The first temperature sensor is positioned at least partially within a cavity formed between a front surface of the head unit and the printed circuit board.