The 10000 Litre Carat AA Silentio Rainwater Harvesting System from GRAF supplies rainwater to your toilets, washing machine and outside taps from a Carat XL underground tank. At 10,000 litres it suits a large household, a holiday let business or a small commercial building.
As a guide, British Standard BS 8515 suggests a tank of around 5% of the rain your roof collects in a year, which for the 10000 litre tank works out at a roof area of roughly 335 square metres. Used for toilets and laundry, it also holds around 18 days of supply for up to 11 people.
How the Carat AA Silentio System Works
A filter cleans rainwater on its way into the tank, and a floating intake then draws water from just below the surface. However, unlike a submersible system, the AA Silentio uses a wall-mounted Aqua Control Centre indoors. This single quiet, insulated cabinet holds the pump, the controls and the mains back-up.
When the tank runs low, the control unit switches to mains water through a built-in air-gap cistern. Therefore mains water never enters the tank or mixes with rainwater, so the system meets UK water regulations. In addition, a digital level indicator shows how much rainwater is left at a glance.
Key Benefits
- Very quiet indoor pump unit, ideal for utility rooms and garages
- Air-gap mains back-up meets UK water regulations
- Digital level display shows the tank level at a glance
- No pump in the tank, so servicing is quick and easy
- Reliable supply to toilets, washing machine and outside taps
What’s Included
- 10,000 litre Carat XL underground tank
- Telescopic dome shaft with 150kg pedestrian lid
- Inlet filter
- Floating intake filter
- Overflow syphon
- Aqua Control Centre wall-mounted pump and control unit with air-gap mains back-up
- Digital level indicator
- Float sensor
Not Supplied
- 100mm duct pipe for the pump hose and cables
- 100mm inlet drainage pipe from the downpipes
- 100mm overflow pipe to a soakaway or surface water drain
- Electrical connection (a qualified electrician should carry this out)
Specification
- Capacity: 10,000 litres (approx. 2,200 gallons)
- Tank: GRAF Carat XL tank with a ribbed body designed for deep burial and heavy ground loads
- Tank dimensions: 3520 x 2240 x 2285 mm (L x W x H, before dome shaft)
- Tank weight: 440 kg
- Loading: Pedestrian as standard, vehicle with the optional traffic lid
- Warranty: 15 years on the tank, 2 years on parts
- Not suitable for drinking water
- Manufacturer: GRAF UK
Optional Extras
- Traffic Telescopic Lid 3.5 Tonne, for driveways, yards and car parks
Delivery
We deliver the 10000 Litre Carat AA Silentio Rainwater Harvesting System free to UK mainland addresses. The tank arrives on a lorry, so you will need to be able to offload it on arrival. In addition, drawings, data sheets and installation guides are available to download on this page.
















