
Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump
The Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump is designed for marine use, providing reliable fresh water delivery. With a 3.0 GPM flow rate and an automatic pressure switch, this pump offers efficient operation for recreational boats, yachts, and other watercraft. Its durable design ensures long-lasting performance, while a built-in thermal overload protection guarantees safety. Ideal for fresh water applications, the Seaflo pump is an essential component for any boat’s plumbing system, ensuring a steady supply for showers, sinks, and other onboard needs.
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Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump
Marine Chandlery: North Shields
Unit G4 Narvik Way
Tyne Tunnel Trading Estate
North Shields NE29 7XJ
United Kingdom

The Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump is designed for marine use, providing reliable fresh water delivery. With a 3.0 GPM flow rate and an automatic pressure switch, this pump offers efficient operation for recreational boats, yachts, and other watercraft. Its durable design ensures long-lasting performance, while a built-in thermal overload protection guarantees safety. Ideal for fresh water applications, the Seaflo pump is an essential component for any boat’s plumbing system, ensuring a steady supply for showers, sinks, and other onboard needs.
The Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump is designed for marine use, providing reliable fresh water delivery. With a 3.0 GPM flow rate and an automatic pressure switch, this pump offers efficient operation for recreational boats, yachts, and other watercraft. Its durable design ensures long-lasting performance, while a built-in thermal overload protection guarantees safety. Ideal for fresh water applications, the Seaflo pump is an essential component for any boat’s plumbing system, ensuring a steady supply for showers, sinks, and other onboard needs.
Description
The Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump is engineered for efficient and reliable freshwater transfer in marine applications. This robust pump operates on a 12V DC power supply, making it ideal for onboard use in boats, yachts, and other watercraft. With a flow rate of up to 3.0 gallons per minute (GPM) and a pressure rating of 35 PSI, the Seaflo 21 Series is designed to accommodate various freshwater needs, from kitchen sinks and showers to general water distribution systems. Key features include an automatic demand system that activates the pump when water is needed, ensuring consistent water pressure without the need for manual switching. The diaphragm design is self-priming, capable of lifting water up to 8 feet, providing flexibility in installation locations. It incorporates thermal and overload protection for enhanced safety and longevity during operation. Typical use cases encompass freshwater systems in marine vessels, RVs, and mobile homes, making it versatile for any off-grid or traveling lifestyle. Built durable for marine environments, the Seaflo 21 Series is resistant to corrosion and built to withstand the rigors of life on the water. Practical benefits for marine users include reduced noise compared to traditional pumps, easy installation options, and low maintenance requirements — all contributing to a seamless freshwater supply experience on board. With its combination of efficiency, reliability, and user-friendly features, the Seaflo 21 Series 12v Automatic Demand Fresh Water Diaphragm Pump is a trustworthy choice for ensuring access to fresh water in any marine setting.
Specification
| Specification | Detail |
|---|---|
| Model | Seaflo 21 Series |
| Voltage | 12V DC |
| Flow Rate | 3.0 GPM (Gallons Per Minute) |
| Pressure | 55 PSI |
| Type | Automatic Demand Diaphragm Pump |
| Ports | 1/2" NPT |
| Weight | 3.5 lbs |
| Dimensions | 9.5" x 5.5" x 4.5" |
| Self-Priming | Yes |
| Applications | Freshwater systems, RVs, boats, and more |
Delivery information
Standard delivery: 3-5 working days
Express delivery: 1-2 working days
Free delivery on orders over £100








