WaterBoost- Slimline EXT
WaterBoost WB-EXT Slimline 150 Mini3 Variable Speed 2501210
- Established 1975
- Trusted by thousands of customers
The WaterBoost WB-EXT Slimline 150 Mini3 is a compact, variable-speed water boosting system combining a 150-litre WRAS-approved slimline tank (600mm dia × 650mm high) with the DAB Esybox Mini3 external pump. Delivering 50 l/min at 3 bar, it brings variable speed performance, WiFi, and voice control to a highly practical low-profile format — ideal for 1–2 bedroom homes where space is restricted.
The Esybox Mini3 sits alongside the tank rather than inside it, providing easy access for servicing and maintenance. The tank connects directly to the mains via the pre-fitted ¾” ball float valve, and the system arrives fully pre-built. At just 650mm tall, it fits under kitchen units, in low cupboards, and in spaces where taller systems cannot.
Supplied with union connections, ¾” ball float valve, 600mm hose, and By-law 30 kit. The tank carries a 5-year warranty and the DAB Esybox Mini3 a 3-year warranty. Please contact us for delivery timescales.
WRAS tank & pump
Only 650mm tall
Variable speed
Direct mains
5yr tank warranty
More about this product
The WaterBoost WB-EXT Slimline 150 Mini3 brings the performance of the DAB Esybox Mini3 to a compact, low-profile tank system. The 150-litre WRAS-approved tank sits at just 650mm tall — fitting under kitchen units, in low cupboards, and in spaces where taller systems cannot — while the external Mini3 delivers 50 l/min at 3 bar with variable speed efficiency. Designed for 1–2 bedroom homes where space is tight but performance matters.
Unlike internal-pump systems, the Mini3 sits neatly alongside the tank. This makes it easy to access for servicing, and means the pump benefits from the full Esybox Mini3 feature set — WiFi via the DConnect app, Google Home and Alexa voice control, and variable speed speed adjustment to match demand. The mains connects directly via the pre-fitted ¾” ball float valve. Fully pre-built, no site assembly required.
5-year tank warranty and 3-year DAB pump warranty. Please contact us for delivery timescales.
Three compact boosting systems for smaller properties. The WB-EXT Mini3 is the cheapest, has more storage, higher flow than the Compact Fixed, and adds WiFi and variable speed. The Powertank COMPACT units are rated to Fluid Category 5 and have a washing-machine-sized form factor that hides behind a cupboard door.
WB-EXT Slimline 150 Mini3 — the best overall choice for potable water boosting at £625 + VAT. More storage (150L vs 125L), higher flow than the Compact Fixed (50 vs 40 l/min), variable speed, WiFi and voice control, named 5yr tank and 3yr pump warranties. Excellent for 1–2 bedroom homes needing low-profile installation with smart features.
Powertank COMPACT 125 Fixed — choose if Fluid Category 5 compliance is required, or if the square washing-machine form factor suits your installation space better than a cylinder + external pump. 40 l/min. £815 + VAT.
Powertank COMPACT 125 Variable — highest flow in this group at 65 l/min with Fluid Category 5 compliance. At £1,355 + VAT it is the most expensive. Choose only if Cat 5 and 65 l/min are both specifically required.
How much does it cost and how is it delivered?
What does “EXT” mean — why is the pump external?
How does the mains connection work?
Is 150L enough storage for my home?
How does the WiFi work?
What warranties are included?
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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