Abstract text

A pumped shower drain system (10) comprises a shower base (12), a waste water unit (14) provided on the shower base (12) and having a waste water inlet (28) and a waste water outlet (30), and a reciprocating water pump (20) for pumping water from the waste water unit (14) to a drain (22). The reciprocating water pump (20) includes: a pump housing (40) having a pump inlet (48) in liquid communication with the waste water outlet (30) of the waste water unit (14), and a pump outlet (50) in liquid communication with the drain (22); first and second inlet valve seals (56, 58) in spaced relationship; and first and second outlet valve seals (84, 86) in spaced relationship. Each set of inlet and outlet valve seals comprise different kinds of valve seals from each other, and are independently closable to close the pump inlet or outlet. Preferably, the inlet valve seals and/or the outlet valve seals have different modes of operation.