WaterBoost – Coffin
WaterBoost WB-Coffin 320 Mini3 Variable Speed 2206210
In stock
- Established 1975
- Trusted by thousands of customers
The WaterBoost WB-Coffin 320 Mini3 is a compact, variable-speed water boosting system engineered to overcome low water pressure or inadequate flow in domestic and light commercial applications. Designed for installations where space is limited, it provides a cost-effective solution while still delivering excellent performance, reliability, and build quality.
The system combines a robust 320-litre WRAS-approved coffin-style tank with the proven DAB Esybox Mini3 booster pump, delivering efficient and consistent pressure boosting of up to 50 litres per minute at 3 bar. This makes it an ideal choice for improving performance to showers, taps, and household appliances without the footprint or complexity of larger boosting systems.
With compact dimensions of 1650mm (L) × 610mm (W) × 500mm (H), the WB-Coffin 320 Mini3 is perfectly suited to installations where height restrictions or access limitations are key considerations. The tank is supplied pre-fitted with a By-law 30 kit and ½” ball valve, and all interconnecting pipework is included as standard.
WRAS tank & pump
500mm height
Direct mains
Pipework included
5.5 bar max
More about this product
The WaterBoost WB-Coffin 320 Mini3 is a compact, variable-speed water boosting system designed for installations where height is restricted. The coffin-style tank lies horizontally at just 500mm tall — fitting under stairs, inside low-ceiling cupboards, and in garages or plant rooms where an upright tank would not.
The mains supply connects directly to the tank via the pre-fitted ½” ball float valve. The DAB Esybox Mini3 variable speed pump draws from the 320-litre WRAS-approved tank, delivering a consistent 50 l/min at 3 bar. The Mini3’s intelligent speed control adjusts continuously to match demand — maintaining stable pressure across multiple outlets simultaneously with low noise and reduced running costs.
Supplied complete with By-law 30 kit, ½” ball float valve, and all interconnecting pipework. WiFi via the DConnect app, Google Home, and Alexa compatible. 3-year DAB pump warranty. Please contact us for delivery timescales.
Three coffin-format boosting systems in the 320–340L range — all connect directly to mains, all WRAS-approved tanks. The key differences are pump type, flow rate, and features.
WB-Coffin 320 Mini3 — the best all-round choice and cheapest of the three at £745 + VAT. Higher flow (50 vs 40 l/min), variable speed efficiency, WiFi and voice control, 3-year warranty. Best for domestic and light commercial potable water use. Note tank is 320L vs 340L for the Powertank options — a negligible real-world difference.
Powertank COFFIN 340 Fixed — choose for Fluid Category 4 compliance or where a commercial-grade fixed-speed system is needed. Includes an integrated 3L pressure vessel. £980 + VAT.
Powertank COFFIN 340 Simplicity — budget Fluid Category 4 option at £900 + VAT, but no integrated pressure vessel — one must be purchased separately. Only 1-year warranty.
How much does it cost and how is it delivered?
How does the mains connection work?
What is the difference between this and the Powertank COFFIN 340 options?
Should I choose the 200L, 320L or 450L WB-Coffin?
How does the WiFi work?
What warranty is included?
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Esybox Mini3 PDFDownload
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Data Sheet PDFDownload
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Manual PDFDownload
Standard delivery:
Standard delivery is free on most orders. Some items may incur a delivery charge depending on weight, size or value. Any applicable charge will be displayed at checkout.
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 £16.50 + 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.
Pallet/Large/Difficult items:
Some large, heavy or difficult to transport items may incur an additional delivery charge. Please contact us for a delivery quote before ordering.
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