FILTERING DEVICE AND METHOD FOR CONTROLLING FILTERING DEVICE

PROBLEM TO BE SOLVED: To provide a filtering device that can perform proper reverse washing operation even when water temperature varies, and to provide a method for controlling a filtering device.SOLUTION: A filtering device 1 includes: a filtering tank 31 storing a filter medium for filtering water passing from a primary side to a secondary side; a drain pipe 34 having main piping 41 connected on a primary side of the filtering tank 31 and sub-piping 43 connected to the main piping 41 in parallel on the primary side of the filtering tank 31; a storage tank 13 for storing water that is filtered by the filtering tank 31; a reverse washing pump 14 for supplying water stored in the storage tank 13 to the secondary side of the filtering tank 31; and an on-off valve 45 provided in the sub-piping 43.SELECTED DRAWING: Figure 1 【課題】水温が変化しても、適切な逆洗運転が可能となる濾過装置及び濾過装置の制御方法を提供すること。【解決手段】濾過装置１は、一次側から二次側へ通過する水を濾過する、濾過材が収容された濾過槽３１と、濾過槽３１の一次側に接続された主配管４１、及び、濾過槽３１の一次側に、主配管４１に並列に接続された副配管４３を有する排水管３４と、濾過槽３１で濾過された水を貯留する貯留槽１３と、貯留槽１３に貯留された水を濾過槽３１の二次側に供給する逆洗ポンプ１４と、副配管４３に設けられた開閉弁４５と、を備える。【選択図】図１