Originally Posted by
tecman
I also completely agree with this. Blowers that the HVAC industry uses, whether axial or radial, draw less HP when they do not deliver airflow. If you block the airflow in a canister vac, the motor speeds up. There are some blowers that will increase HP, but they are specialty industrial apps for high head or vacuum.
It is either a bad design on the part of the mfg, or a bad (batch) of motors, or low voltage, or a bad cap or some combination of these. Also as was said, any HVAC motor is certainly rated for 100% duty cycle.
paul