WaterBoost Slimline - Variable Speed
The WaterBoost Slimline — Variable Speed range is a cost-effective, space-saving solution to low water pressure or flow. At 600–700 mm wide it fits through a standard doorway and tucks neatly under the stairs, in a garage or in a utility room — ideal where floor space is at a premium in new or existing properties.
Its variable speed pump delivers up to 5 bar and 100 l/min, generating only the pressure your mains can’t — an energy-efficient, high-quality solution that keeps installation cost down. Built for 3–5 bedroom homes with poor pressure and limited room to spare.
speed
Why choose the Slimline range?
Key specifications
| Pump type | Variable speed — only boosts the shortfall |
| Max pressure | Up to 5 bar |
| Max flow | Up to 100 l/min |
| Width | 600 mm (700 mm on the 500 L) — fits through a standard doorway |
| Siting | Under stairs, garage or utility room |
| Best for | 3–5 bedroom homes with poor pressure and limited floor space |
Where floor space is tight but performance can’t be, the WaterBoost Slimline Variable Speed range delivers strong, efficient pressure and flow in a footprint that fits through any doorway. Choose your model below.
2 products
The WaterBoost WB-INT Slimline 300 is a complete, pre-built variable-speed water boosting system designed to solve low water pressure and flow in 3–5 bedroom homes.…
The WaterBoost WB-INT Slimline 500 is a complete, pre-built variable-speed water boosting system for high-demand 3–5 bedroom homes. A 500-litre WRAS-approved upright slimline tank pairs…
Frequently Asked Questions
Quick answers to common questions about the WaterBoost Slimline – Variable Speed. 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.