1. Introduction
This manual provides essential information for the safe and efficient operation, installation, and maintenance of your WASSERMANN 4WDP5-55-115V Water Pressure Booster Pump. Please read these instructions thoroughly before installation and use to ensure proper function and longevity of the product.
The WASSERMANN 4WDP5-55-115V is a self-priming water pressure booster pump designed to provide consistent water pressure for various applications, including RVs, kitchens, bathrooms, marine vessels, yachts, and garden systems. It operates on 115V AC power and features a pressure switch for automatic operation.
2. Safety Information
WARNING: Failure to follow these safety instructions could result in electric shock, fire, or serious injury.
- Always disconnect power before performing any installation, maintenance, or troubleshooting.
- Ensure the power supply matches the pump's voltage requirements (115V AC).
- Do not operate the pump with damaged electrical cords or plugs.
- Install the pump in a dry, well-ventilated area, protected from freezing temperatures and direct sunlight.
- Ensure all plumbing connections are secure and leak-free to prevent water damage.
- This pump is designed for pumping clean water only. Do not use it for flammable liquids, corrosive chemicals, or water containing abrasive particles.
- Keep children and unauthorized personnel away from the pump during operation.
3. Package Contents
Verify that all items listed below are included in your package:
- 1 x WASSERMANN 115 Volt Water Pressure Booster Pump
- 1 x User Manual (this document)
- 2 x 1/2" Barbed Hose Adaptors
- 1 x 1/2" Male Thread Hose Adaptor
- 1 x Filter (Strainer) for Debris

Figure 3.1: The WASSERMANN 4WDP5-55-115V pump with its included accessories, including various hose adapters and a debris filter.
4. Setup and Installation
Proper installation is crucial for the pump's performance and safety. If you are unsure about any step, consult a qualified professional.
4.1 Mounting the Pump
- Choose a stable, level surface for mounting. The pump should be installed below the water source if possible to aid in priming.
- Secure the pump using the integrated mounting feet. Ensure there is enough space around the pump for ventilation and maintenance.

Figure 4.1: The pump features sturdy mounting feet for secure installation.
4.2 Plumbing Connections
- Identify the inlet and outlet ports on the pump. The inlet typically has an arrow indicating water flow direction.
- Install the included filter (strainer) on the inlet side of the pump to prevent debris from entering and damaging the pump. Hand-tighten only.

Figure 4.2: The included strainer filter should be installed on the pump's inlet to protect against debris.
- Connect your water supply line to the inlet and the distribution line to the outlet using the appropriate hose adaptors provided. Ensure all connections are tight to prevent leaks.
- The pump is self-priming, meaning it can draw water from a source without needing to be manually filled with water first.

Figure 4.3: Example plumbing diagram illustrating the pump's integration into a typical water system.
4.3 Electrical Connection
- Ensure the pump's power cord is easily accessible.
- Plug the 115V AC power cord into a standard wall socket.

Figure 4.4: Connect the pump to a standard 115V AC power outlet.
5. Operating Instructions
The WASSERMANN 4WDP5-55-115V pump is designed for automatic operation.
- Once connected to power and water lines, the pump will automatically start when a tap or fixture is opened, causing a drop in water pressure.
- The pump will automatically stop when the tap or fixture is closed and the system pressure reaches the shut-off point (55 PSI).
- The integrated pressure switch and bypass switch work together to maintain consistent water flow and prevent frequent starts/stops, especially with small flow demands.

Figure 5.1: The pump features an automatic pressure switch for demand-based operation.
6. Maintenance
Regular maintenance ensures optimal performance and extends the life of your pump.
- Inspect Connections: Periodically check all plumbing and electrical connections for leaks or damage. Tighten as necessary.
- Clean Strainer: Regularly inspect and clean the inlet strainer to remove any accumulated debris. A clogged strainer can reduce pump performance and lead to damage.
- Winterization: If the pump is installed in an area subject to freezing temperatures, it must be drained completely or protected with non-toxic antifreeze to prevent damage.
- General Cleaning: Keep the exterior of the pump clean and free from dirt and dust.

Figure 6.1: Internal components of the pump, including the 100% solid copper motor, shaft seal, diaphragm impeller, pump body, and pressure/bypass switch.
7. Troubleshooting
If you encounter issues with your pump, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| Pump does not start | No power supply Clogged inlet/outlet Faulty pressure switch | Check power connection and circuit breaker Inspect and clear any blockages Contact customer support |
| Low water flow/pressure | Clogged strainer Air in the system Restrictive plumbing | Clean the inlet strainer Bleed air from the system by opening all faucets Ensure plumbing lines are adequately sized |
| Pump runs continuously or cycles frequently | Leak in the system Pressure switch malfunction Insufficient water supply | Check all connections and fixtures for leaks Contact customer support Ensure adequate water source |
| Water leaks from pump | Loose connections Damaged seals/housing | Tighten all plumbing connections Contact customer support for replacement parts or service |
8. Specifications
- Brand: WASSERMANN
- Model: 4WDP5-55-115V
- Material: Plastic
- Product Dimensions (L x W x H): 9.26" x 4.92" x 4.33"
- Power Source: Corded Electric
- Item Weight: 6.8 Pounds
- Maximum Flow Rate: 5 Gallons Per Minute (GPM)
- Maximum Lifting Height: 125 Feet
- Voltage: 115 Volts AC
- Shut-off Pressure: 55 PSI
- Included Components: 1 Pump, 4 Plastic Adapters

Figure 8.1: Dimensional overview of the WASSERMANN 4WDP5-55-115V pump.

Figure 8.2: Product label displaying model number, voltage, flow rate, and pressure specifications.
9. Warranty and Support
For warranty information, technical support, or to inquire about replacement parts, please contact WASSERMANN customer service or refer to the official WASSERMANN website. Keep your purchase receipt as proof of purchase.