Abstract: A damper actuator for use in a ventilation system typically used in an air conditioning system to activate the damper or damper assembly in response to an electrical signal. More particularly, a heat motor rotatably coupled at one end to a lever or lever assembly and rotatably coupled at its other end to a stationary frame. A spring may also be coupled to the lever or lever assembly and to the frame when necessary to provide a force to return the lever or lever assembly to its initial position or configuration. By means of a rotatable coupling at each end of the heat motor, stresses transverse to the longitudinal axis of the heat motor, are substantially eliminated and the operational life of the heat motor is significantly increased.