PUMP DEVICE AND LIQUID CIRCULATION DEVICE EQUIPPED THEREWITH

PROBLEM TO BE SOLVED: To simply perform pump output adjustment corresponding to piping resistance when the piping resistance is known.SOLUTION: The pump device is installed at a midway part in the circulation passage having a predetermined piping resistance for circulating liquid. The pump device includes a motor control unit 3 for performing PWM control of the operation of a motor 4 for driving the pump, a piping resistance detecting unit 1 for detecting the piping resistance in the circulation passage, and a duty ratio instruction unit 2 having a duty ratio set in advance corresponding to a plurality of specified piping resistance for instructing and outputting the duty ratio corresponding to the piping resistance detected by the piping resistance detecting unit. The motor control unit 3 drives the motor at the duty ratio instructed by the duty ratio instruction unit 2.