The DP pumps are regarded as one of best pumps for deep well. In fact they consist of two pumps connected in series ,ejector-pump and the other is centrifugal pump. The ejector pump is lowered in well and connected to centrifugal pump body by two pipes .These pumps are suitable for pumpingclean water and chemically non-aggressive fluids. They are extremely reliable,economical and simple to use,finding many use in domestic applicationsand the automatic distribution of water from small and medium-sized surge tanks  form an automatic booster systems to supply water .The most remarkable character is that they can be used to supply clean water from extremely deep well . TO ensure adequate counter-pressure ,it is always to install a foot value with a filter on the suction opening .