System and method for determining filter condition

摘要

A system and method for determining the condition of a filter in a forced air filtration system includes a blower motor and a fan mounted for rotation with an output shaft of the blower motor. A load sensor is operably connected to the blower motor for monitoring an electric load of the motor. As the filter becomes increasingly laden with airborne particles, the electric load changes. The load sensor generates a load value dependent on the electric load of the motor which is compared to a predetermined value. When the load value reaches the predetermined value, a signal is generated indicative of a filter change condition.