WASHER

PROBLEM TO BE SOLVED: To provide a washer capable of suppressing the overflow of drain water to the outside of the machine when the discharge filter is clogged and needs to be detached.SOLUTION: A washer 100 comprises a washing tub 2 connected to a drainage tube 81 via a drain part 80. The drainage tube 81 connects to a filter case 82 containing a discharge filter 83 detachable from the housing 1. The filter case 82 connects to a drainage hose 85 via a drainage valve 84. An operation control unit 16 is configured to: determine whether the drainage filter 83 is clogged or not on the basis of variation of water level of washing water detected by a water level sensor 89; display on an operation panel that it is clogged if it determines that the drainage filter 83 is clogged; and open the drainage valve 84 with an alarm. The operation control unit 16 is configured to close the drainage valve 84 if a filter sensor 93 detects that the drainage filter 83 has been inserted.