The invention provides blower housings for air handlers and hot air furnaces which are made from molding compounds that allow for wide flexibility in molding complex configurations so as to improve blower efficiency, which improve manufacturing efficiency and safety and provide suitable mechanical properties, safety in use, and sound dampening. In the formulae, each of R1 and R4 independently represents a hydrogen atom, an aryl group, or an alkyl group, and among these, an aryl group is preferable. At this time, temperature information Tr is detected by the sensor and is corrected taking into account the vehicle speed detected by a vehicle speed sensor and an engine temperature detected by an engine temperature sensor.