The Multi-Stage Pump 1HP, 110/220 PH is a horizontal multi-stage centrifugal booster pump designed for water treatment and distribution applications requiring sustained high-pressure output. It accepts either 110V or 220V single-phase power – field-selectable at installation. At 1 horsepower, the multi-stage impeller design delivers substantially higher discharge pressure than a single-stage pump of equivalent motor size, right for systems that need 60 to 100+ PSI at the outlet – whether that’s fighting back-pressure from RO membranes or pushing water through long distribution runs.
Typical Applications
- Post-tank repressurization for whole-house RO systems: Gravity-fed or atmospheric storage tanks drop pressure to near zero. This pump restores working pressure (typically 60-80 PSI) before water enters house distribution lines.
- Feed water pressure boost for commercial RO trains: Municipal or well supply with insufficient inlet pressure starves RO membranes and reduces recovery. This pump raises feed pressure to the required operating range.
- General pressure boosting in water treatment systems: Suitable anywhere in a treatment train that requires a pressure increase between stages – multimedia filters, carbon vessels, UV systems, or distribution headers.
- Remote and off-grid installations: Dual-voltage compatibility works with both standard grid power and generator or inverter supplies common in rural or temporary water supply setups.
Multi-Stage Design
Multi-stage centrifugal pumps use several impeller stages in series. Each stage adds to the discharge pressure, so total head at the outlet is the sum of all stages rather than the output of a single impeller. The result is higher working pressure at a given flow rate without a larger motor. Multi-stage pumps also run quieter and hold efficiency better at high-pressure duty cycles than single-stage designs, which lose efficiency quickly above their design point.
Installation and Electrical
- Dual voltage: 110V/220V field-selectable via internal wiring. Confirm supply voltage before wiring; incorrect voltage damages the motor.
- Electrical connection: Requires professional installation by a licensed electrician. Wire to a dedicated circuit with appropriate breaker sizing for the motor amperage at selected voltage.
- System integration: Connect through a pressure switch or pump controller for automatic start/stop based on system demand. Compatible with AMPAC commercial RO systems and custom water treatment assemblies. Verify inlet and outlet port sizing against your system plumbing before ordering.
Sizing Note
Match pump selection to your system’s actual flow rate (GPD or GPM) and required discharge pressure. Oversizing a booster pump wastes energy, generates excess heat, and shortens pump and seal life. Undersizing restricts flow and starves downstream equipment. For sizing assistance specific to your RO system or water treatment train, contact AMPAC technical support at (385) 530-1026.
Related Resources
- Commercial Reverse Osmosis Systems — full range of commercial RO for restaurants, clinics and offices
- Industrial RO Systems — higher-capacity options for industrial and municipal applications
- Get Expert Help — speak with a water treatment specialist for sizing and configuration
AMPAC Water Systems designs and manufactures advanced water treatment solutions for commercial, industrial, and municipal applications. From RO systems and PFAS removal to zero liquid discharge and smart water technology — engineered for your needs.




