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WaterBoost- Slimline EXT

WaterBoost WB-EXT Slimline 500 Mini3 Variable Speed 2503210

Our Price £924.00 Inc VAT £770.00 Ex VAT
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  • Established 1975
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The WaterBoost WB-EXT Slimline 500 Mini3 is a high-storage variable-speed water boosting system for 3–5 bedroom homes. A 500-litre WRAS-approved slimline tank (700mm dia × 1500mm high) pairs with the DAB Esybox Mini3 external variable speed pump, delivering 50 l/min at 3 bar with WiFi, DConnect app, and Google Home and Alexa voice control.

The Esybox Mini3 sits alongside the tank rather than inside it — keeping the pump fully accessible for servicing and maintenance at any time. The tank connects directly to the mains via the pre-fitted ¾” ball float valve, and the system arrives fully pre-built with no site assembly required.

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.

50l/min
@ 3 bar
500L
Tank storage
45dB(A)
Ultra quiet
3yr
Pump warranty
WiFi · Google · Alexa
WRAS tank & pump
Variable speed
5.5 bar max
Direct mains
5yr tank warranty
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Frequently Asked Questions

Quick answers to common questions about the WaterBoost WB-EXT Slimline 500 Mini3 Variable Speed 2503210. For technical specifications, see the product details above; for sizing or installation advice, contact our team. If you have any other questions, we're happy to help.

What is a mains pressure boosting system?

A mains pressure boosting system increases the pressure and flow of water from the incoming mains supply into a property. It typically combines a pump and a storage or expansion tank, drawing water from the mains and delivering it to taps, showers and appliances at a stronger, more consistent pressure. They are used where the incoming mains is too weak to serve modern outlets reliably.

When do I need a mains booster pump?

You normally need a mains booster if static mains pressure is below 1.5 to 2 bar, if showers run weakly when other taps are open, or if combi boilers struggle to deliver hot water. Anglian Pumping recommends checking static pressure at the stop tap before specifying a system, then choosing a model rated for the number of bathrooms and outlets in the property.

What size mains booster do I need for my home?

Sizing depends on the number of bathrooms, the type of fittings and the static mains pressure. As a guide, a 1 to 2 bathroom property with combi boiler or single shower often needs 1.6 to 3 bar boost. A 2 to 3 bathroom property typically needs 3 to 4.5 bar with an integral break tank. Larger homes need a tank-and-pump system such as the DAB Esybox with Esytank or a Powertank set.

What is a water booster pump?

A water booster pump increases the pressure of an existing water supply to give stronger flow at taps, showers and appliances. It can be a small inline pump fitted to the incoming mains, or a larger pump and tank set that draws from a break tank to feed the whole house. Boosters do not create water – they raise the pressure of the water already coming in.

What is the difference between an inline booster and a tank-and-pump booster?

An inline booster connects straight onto the incoming mains and is limited to 12 litres per minute under UK water regulations – examples include the Salamander HomeBoost and WaterBoost WB-Compact. A tank-and-pump booster, such as the Grundfos Home Booster or DAB Esybox with Esytank, draws from a break tank and can deliver much higher flow rates for larger homes with multiple bathrooms.

What is a variable speed booster pump?

A variable speed booster uses an inverter to adjust pump speed in real time to match demand. It maintains constant pressure as outlets open and close, runs more quietly than a fixed-speed pump and typically saves up to 50 per cent of the energy a fixed-speed equivalent would use. The DAB Esybox, DAB Esybox Mini 3 and Grundfos Scala2 are common variable speed examples.