Wassermann 3WDP4-45-12V RV Water Pump, 12V, 4 GPM, 45 PSI

A 12V DC motor and self-priming design give the Wassermann 3WDP4-45-12V a practical role in RV and camper freshwater systems. It delivers up to 4 GPM at a 45 PSI pressure setting for everyday water use at sinks and other connected fixtures.

The built-in pressure switch starts the pump when a tap is opened and stops it when the tap is closed. That automatic operation makes it a convenient choice for a pressurized water setup without manual pump switching.

Its 12V power source suits RV, marine, camping, yacht, and garden applications where a compatible 12V supply is available. The pump is also presented as a replacement option for RV water systems.

Technical overview

The combination of self-priming operation and an automatic pressure switch is designed for on-demand water delivery. In a camper, for example, opening a sink faucet prompts the pump to run, while closing the faucet signals it to stop. This setup is useful for regular freshwater access at a sink or bathroom fixture. A manually operated pump may suit a setup where water is controlled by switching the pump itself, this model is designed to respond to tap use instead.

• Voltage: 12 volts DC
• Flow rate: Up to 4 GPM
• Pressure: 45 PSI
• Maximum lifting height: 98 feet
• Inlet/outlet: 1/2 inch
• Dimensions: 8.15 x 5.12 x 4.86 inches
• Material: Plastic

The package includes the pump, two 1/2-inch barbed hose adapters, one 1/2-inch male-thread hose adapter, a debris filter, and a user manual. The supplied fittings and filter support connecting the pump to a freshwater line and help keep debris out of the system.

Buyer feedback commonly highlights installation, fit, water pressure, and use as a replacement pump, including under-sink applications. Experiences with durability and noise are mixed: some buyers report early failures, while descriptions of operating noise vary. These reports reflect individual experiences, not a guarantee of a particular outcome.

Best use cases

This pump is suited to RV and camper owners setting up or replacing a 12V freshwater pump for sink and bathroom use. Its automatic pressure switch is useful when the system should respond to opening and closing a tap, and its stated flow and pressure provide concrete reference points when choosing a pump for a water system.

The listed applications also include marine, camping, yacht, and garden setups. For installation, match the system’s 12V DC supply and 1/2-inch inlet and outlet connections to the pump and fittings. The manufacturer also identifies a 12V battery or an RV/camper cigarette lighter socket as power options.

Included in the package

The kit contains one 12V RV water pump, two 1/2-inch barbed hose adapters, one 1/2-inch male-thread hose adapter, one debris filter, and one user manual. Together, these components provide the main pump, connection fittings, and filter for a freshwater installation.

Questions before you buy

How does the pressure switch operate? The pump starts automatically when you open a tap and shuts off when you close it, supporting on-demand water use.

What power supply does it use? It runs on 12V DC. The stated power options include a 12V battery or a cigarette lighter socket in an RV or camper.

What connections are specified? The inlet and outlet are 1/2 inch. The package includes two 1/2-inch barbed hose adapters and one 1/2-inch male-thread hose adapter.

Buying verdict

The Wassermann 3WDP4-45-12V is a practical choice for a 12V RV or camper freshwater setup that calls for self-priming operation, a 45 PSI pressure setting, and automatic response to tap use. Its stated flow rate, connection size, and included fittings make it easier to assess for a replacement or new installation, while the pressure switch supports hands-off operation during everyday sink and bathroom use.