PURPOSE: To prevent a user from being given with the discomfortable feeling due to the deterioration of function by installing a controller for disabling the circulation operation when a pressure detection sensor installed in the vicinity of a filter inlet part shows the pressure over a certain value and easily detecting the maintenance timing for cleaning and replacement of a filter.

CONSTITUTION: When a bathtub 11 is filled with water and an operating switch 28 on a bathtub operating panel 27 is turned ON, a control part 23 receives the signal of an operation part, and a circulation pump 16 is driven. The bath water passes through a filter device 18, and a potion A is filtered and violently jetted into the bathtub 11 from a jet nozzle 15, and the jet gas foam operation for giving a proper stimulus onto the body of a human body is carried out. At this time, a pressure sensor 22 detects the pressure of the circulation water immediately before the introduction to the filter device 18 in a water circuit 13, and when the pressure increase exceeds a prescribed value, the controller 23 receives the pressure information detected by the pressure sensor 22, and the operation of the device is suspended, and an inspection lamp is switched from flashing to the all-time lighting, and the maintenance for the filter by the user is facilitated.