WaterBoost INground
The WaterBoost INground — range puts your entire boosted water system out of sight and out of earshot. A buried potable tank stores the water, a fully submersible DAB Esybox Diver sits on the tank base, and a small white kiosk above ground holds the consumer unit and sockets — leaving nothing inside the house to find space for.
The Diver's built-in variable speed drive delivers up to 5.5 bar and 120 l/min, holding steady pressure as taps and showers open and close. Ideal for larger homes, barn conversions and properties with no room indoors for a break tank.
Why choose the Underground range?
Key specifications
| Pump | DAB Esybox Diver 55/120 — 7" submersible, variable speed, WRAS approved |
| Pressure | Pre-set 3 bar, adjustable 1–5.5 bar |
| Max flow | Up to 120 l/min (7.2 m³/h) |
| Tank | Underground potable tank, one-piece HDPE, 10-year guarantee |
| Power & control | 230 V single phase; white kiosk with consumer unit and 2 sockets (pump + DConnect Box 2) |
| Monitoring | DConnect Box 2 and app — pressure, alarms and tank level |
| Best for | Larger homes, conversions and properties with no indoor space for a break tank |
Where there's no room indoors but you still want strong, steady pressure, the WaterBoost INground — Esybox Diver range hides the whole system in the garden and keeps the house quiet. Choose your tank size below.
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3 products
The WaterBoost Inground 800 hides your whole booster system in the garden. An 800 litre buried potable tank and a fully submersible DAB Esybox Diver…
The WaterBoost Inground 1500 hides your whole booster system in the garden. A 1,500 litre buried potable tank and a fully submersible DAB Esybox Diver…
The WaterBoost Inground 2500 hides your whole booster system in the garden. A 2,500 litre buried potable tank and a fully submersible DAB Esybox Diver…
Frequently Asked Questions
Quick answers to common questions about the WaterBoost INground. 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.