JT-750 Series DC Solar Water Pump: Threaded Pump for Solar Heater and Underfloor Heating Systems

Designed for integration into renewable energy and hydronic heating setups, the JT-750 series DC water pump provides a dedicated solution for circulating clean water. Its low-voltage DC operation (12V or 24V) makes it directly compatible with off-grid solar PV systems or battery banks, eliminating the need for an inverter. This pump serves a specific purpose: boosting flow in solar thermal collector loops or moving warm water through underfloor heating pipes. With a focus on practical installation, it is offered in multiple pre-threaded variants to match common plumbing sizes, ensuring a more straightforward connection process without requiring additional adaptors for many systems.

Features and Construction

The pump's design centres on reliable water transfer in closed-loop applications where consistent, low-maintenance operation is valued. Its construction and specifications are aimed at fulfilling the demands of solar thermal and domestic heating circuits, which typically involve clean, non-abrasive water.

Material and Build

The pump body and key components are moulded from engineering plastic. This material selection provides corrosion resistance, which is beneficial in water-carrying applications, and contributes to the unit's light overall weight of 0.18kg. The drive mechanism is electric, with a horizontally oriented pump shaft. The impeller structure is semi-open, and it operates on a jet pump principle, which is a type of centrifugal pump effective for generating flow. This design, combined with the stated non-blocking performance, indicates suitability for systems with filtered, clean water to prevent internal clogging.

Size and Practical Fit

Physical connection is facilitated by threaded ports, with options for either 20mm or 25mm suction and outlet diameters. The model numbering (B4, B5, D4, D5) corresponds to these different threaded configurations. This variety allows installers to select the pump that matches their existing pipework. The compact nature implied by its weight and its horizontal shaft position suggests it can be mounted in line with piping without requiring excessive space.

Uses and Placement

This pump is categorised as a process pump for conveying clean water. Its performance parameters guide its ideal placement within specific systems, focusing on efficiency and practical integration.

Event or Professional Use

In professional or installed renewable energy systems, this pump finds its primary role. For solar water heating installations, it can act as the circulation pump that moves heat transfer fluid (water) from the rooftop collectors to the storage tank, improving system efficiency. In underfloor heating systems, it serves as a booster pump to ensure even heat distribution across all circuits, particularly in larger areas or multi-loop setups where the primary manifold pump may need assistance.

Everyday Home Use

For the homeowner with a solar thermal system or a hydronic underfloor heating system, this pump represents a critical component for automated operation. Once installed and connected to a suitable DC power source—such as a dedicated solar panel with a charge controller and battery—it works continuously with minimal user intervention. Its low power draw (0.015-0.035kW) aligns with energy-saving goals for domestic hot water and space heating.

Benefits and Buying Value

The value of this pump lies in its specialised application, direct compatibility with DC power sources, and the flexibility offered by its model variants. It addresses specific technical requirements rather than serving as a general-purpose water pump.

Reuse and Low Maintenance

The engineering plastic construction is resistant to corrosion from water, promoting longer service life without degradation from rust. The non-blocking design philosophy suggests internal clearances are managed to reduce the risk of fouling from small particles, potentially lowering maintenance needs. As a dedicated system component, it is designed for long-term, continuous duty within its specified performance envelope of 1.2m³/h flow and 3-7m head.

Why Choose This Product

This pump is selected when a DC-powered, threaded circulation pump is required for a solar thermal or underfloor heating application. The key decision factors are the voltage (12V or 24V), the required flow and head (1.2m³/h, 3-7m), and the thread size needed for your plumbing (20mm or 25mm, as indicated by the B4/B5/D4/D5 model code). It provides a ready-made solution that integrates directly with DC power supplies and standard threaded piping, removing the complexity of adapting a generic AC pump.