WaterBoost Compact
WB-Compact 4.5 ACW1 – Accumulator Booster Pump (Wall Mounted)
In stock
- Established 1975
- Trusted by thousands of customers
WB-Compact 4.5 ACW1 – Digital Accumulator Booster Pump (Wall Mounted)
The WB-Compact 4.5 ACW1 is a digitally controlled, wall-mounted accumulator booster pump designed to deliver smooth, reliable water pressure when used with external accumulator or pressure vessels. Using advanced variable-speed inverter technology, it automatically adjusts output to boost pressure up to 4.5 bar, ensuring consistent performance across showers, taps, and appliances.
Designed for space-saving wall installation, the ACW1 is ideal where floor space is limited or a neat, elevated mounting solution is preferred. It is fully compatible with both vertical and horizontal accumulator vessels, including systems from GWS, WaterBoost, Lowara, Grundfos, and Stuart Turner, and can be installed independently of the vessel for maximum layout flexibility. Pressure settings are easily adjusted via the integrated LCD display.
WRAS approved and exceptionally quiet in operation, the WB-Compact 4.5 ACW1 also features built-in Wi-Fi connectivity, enabling remote control through the DConnect app. Wireless updates and optional voice control integration provide a modern, future-ready solution for intelligent pressure boosting in accumulator-based systems.
More about this product
Key Features
Improved – Features a new three-rotor hydraulic design with wireless update capability, allowing future performance and functionality enhancements.
Constant – Advanced inverter technology automatically regulates pump speed to maintain smooth, consistent water pressure.
Efficient – Variable-speed motor technology delivers energy savings of up to 50% compared with conventional fixed-speed pumps.
Quiet – Housed in a sound-absorbing casing with anti-vibration design, operating at just 45 dB(A) at 1 metre.
Simple – Designed for straightforward wall-mounted installation, intuitive setup, and easy day-to-day operation.
Compact – Space-saving wall-mounted footprint measuring 439 × 263 × 236 mm (H × W × D) and weighing only 15 kg, ideal for tight installation spaces.
Reliable – WRAS approved for potable water use and backed by a three-year manufacturer’s guarantee.
Standard delivery:
Standard delivery is free for all orders except for some low cost/low margin items where standard delivery is £6.75. Some difficult to transport goods also have a varying carriage charge applied.
Please contact us for the estimated standard delivery times of the products that we have in stock, by dropping us a message on our Whatsapp or Live chat.
Deliveries will typically be made between 7am and 6pm, Monday to Friday (excluding public holidays).
Next day delivery:
Next working day delivery is available for a £15.00 + vat delivery charge.
Orders must be placed before 12 noon to qualify for next working day delivery. Orders placed after 12 noon on Thursday but before noon on Friday will be delivered the following Monday. Orders placed after 12 noon on Friday will be delivered on Tuesday.
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