Abstract: A reverse osmosis water purification system that incorporates a high torque low speed motor to drive a pump, such that the pump can continuously pump water from a source of water to an osmotic membrane. The system may have a reservoir to store the purified water as it is pumped through the osmotic filter. The system can also have a transformer and rectifier to convert and rectify an alternating electrical power source to 24 volt DC power for the motor. The transformer having a higher impedance than the motor such that the transformer acts as a current limiter in the event the motor stalls. The pump has an internal pressure relief valve operatively connected to the inlet of the pump housing. The relief valve opens when the output pressure of the diaphragm piston reaches a predetermined valve. The relief valve allows the high pressure water to flow back into the housing inlet creating a flow loop from the inlet back to the water source.