PURPOSE: To obtain an excellent filtration performance from the beginning in a device for circulating and cleaning the hot water in a bathtub by positively propagating the microorganism in the biological filter medium of a biological filtration means.
CONSTITUTION: The hot water in a bathtub 1 is circulated and jetted by a first pump 6 through a solenoid valve 7 to filter the hot water in the bathtub 1 by a filtration means 9 connected to the pump 6 in parallel, and the hot water in the bathtub 1 is further biologically filtered by a biological filtration means 16 connected to the solenoid valve 7 in parallel. The biological filter medium 30 of the means 16 or a heater 31 set in a biological filtration pipeline is formed with a far IR radiator.
SAKAI MAKOTO
SHIMOKAWA SEIJI
YAMAGUCHI MASUO
