Full Product Details
Graf Carat tank 3750 litre, Garden System 1 underground rainwater harvesting KIT. The tried and tested Carat from Graf, supplied complete as a kit for use as a garden rainwater harvesting system.
The images above show some components of the Carat System. Excavation and electrical connections should only be attempted by qualified personnel. For further images that give the scale of the product and show some of the fittings please click here .
Graf Carat tank 3750 litre, Complete System 1 underground KIT includes a 3750 litre underground tank, Optimax Pro filter, Series 3 pump and the accessories needed to deliver clean rainwater to a garden tap. Some standard external pipework and connectors will be needed but are not included in the kit as the location of the system will determine the amount of pipework required.
Why buy this system?
- Feeds garden taps for all outdoor water use
- Prefiltered rainwater delivered to the underground tank
- Quiet (pump submerged)
- Pressure sensitive pump only works when tap opened
- Lifting kit not necessary - can be man-handled onto the site
- Exceptionally strong but light two piece Duralen moulding
- Time tested and backed by a 15 year manufacturer warranty
- Tank construction allows for manoeuvre into less accessible locations -even though doorways
- Components precision made and matched for fast assembly
Graf Optimax Pro filter included as standard In response to customer demand, we have included the Graf’s Optimax Pro filter which fits neatly inside the turret of the Carat tank. With its integrated overflow siphon and inlet calming device, we no longer need to cut holes in the turret other than those provided by Graf in the moulding.
The Optimax Pro Filter is self cleaning - water arriving across the filter mesh pushes excess debris and leaves to the overflow. The optional extra hose connector permits you to connect a hose and wash it through more thoroughly from time to time. We find the alternative Universal Filter 3 leaves the debris and leaves sitting in the filter basket so the user is obliged to open up the manhole cover of the turret, get the basket out and dispose of the leaves and debris somewhere - its a bit like a teabag!. This might be a chore too many in a busy garden, so the Optimax Pro is our preferred choice. You might lose up to 5% of the rain water but it is cleaner and removes the leaf debris away to the soakaway or drain.
External HDPE Rainwater Pipe included. It is important to identify a source of a water supply. Untreated rainwater is not for human consumption and so water companies are recommending (and in some cases requiring) that Black and Green HDPE pipe is used for piping rainwater from the tank to the point of use - eg. garden tap. The point of use should be clearly labelled to show that rain water is the source. We include 25mm black and green hdpe pipe and labels with this kit with the option to buy further rolls of pipe.
If you are referring to the Graf catalogue or brochure, this kit from RainWater Harvesting is the equivalent to the Graf Eco Plus Package; our kit includes items 1) the Tank 2) the dome or “turret” and 3) Filter package 3. In place of the Graf pump package we provide the high quality, popular and ultra-reliable Series 3 submersible pump, and a inline filter to take the cleanest water first.
What comes with this kit?
In the kit version, collated for you by RainWaterHarvesting.co.uk, you get the tank, the Optimax filter pack and the accessories listed below.
|Components list for Graf Carat tank 3750 litre GUK1|
|Product Code||Product Description|
|GF-372002||Graf Carat tank, underground 3750 litre|
|GF-371001||Carat dome (turret)|
|GF-371010||Carat lid, telescopic, made of PE (green)|
|GF-330192||Calmed inlet (into base of tank)|
|GF-330108||Overflow siphon (high water level outlet, fits filter)|
|GF-371033||Carat 3750 accessory pack including tank sealing kit|
|GF-375021||Carat tank dome sealing kit|
|GF-340037||Graf Optimax Pro Filter|
|RWH-HYD01||Series 3 Submersible pump and inline filter from Hydroforce Pumps Ltd|
|RWH-HDPE25/25||Rainwater pipe HDPE 25mm diameter 25 metre coil|
|Delivery||Haulage, UK mainland included (Highlands & Islands on request)|
|GF-372002-GUK1||Complete Underground kit for domestic use|
Options (please phone for availability and price)
- Self-cleaning hose connection kit for the Optimax filter
Upgrade this Kit - to a 'Rain Director' intelligent automated water management system in place of the pump. For more information please click here
Upgrade this Kit - to a 'Rain Manager' fully automated water management system in place of the pump. For more information please click here
1) Bit more leeway on the tank depth: Opt for a Maxi sleeve giving an extra 100mm of adjustment (see above) Product ID: GF-371011
2) Support car traffic: (but not trucks and HGVs) when fitted with the optional dome and cast iron lid. Contractors often ask us the dimensions of the turret. The Vehicle loading lid can be found here Product ID: GF-371020
- Height variable between 750-1050 mm.
- Maximum tilt 5%.
- Cast iron cover.
- Child safety lock.
- Dark Grey.
3) Deeper holes: You can compensate for a deep hole with a tank turret sleeve extension Product ID: GF-371003 which extends the height of the pedestrian dome shaft PE lid by 1000-1500mm
Shipping, assembly and installation
Like the Graf Hercules, the Carat comes in two halves so you can carry it through a doorway as narrow as 80cms (and so we can stack many of them on one pallet for bulk transport). A centering bolt makes assembly accurate and the quick connections ensure there are no leaks between the two sections... and yet you can disassemble it if you like. The material used is a PE variant called Duralen. The Carat tank can support pedestrian and car traffic (but not trucks and HGVs) when fitted with the optional dome and cast iron lid. The complete installation and maintenance instructions for the Carat tanks are available on demand from firstname.lastname@example.org but are not available except to purchasers.
The Graf Carat tank is the largest tank of its kind in the world to be manufactured by injection compression moulding. This technique provides the tank with unbeatable stability and ensures that each component is produced with the highest accuracy. Graf have invested €20m in their factory near Freiburg for the Carat range, introduced in early 2007.
- Designed for underground mounting
- (German manufactured, TÜV safety-tested
- Patented quick connection (no screws required for mounting)
- Permanently watertight: durably sealed thanks to solid profile sealing
- Easy transport thanks to low weight and practicable size
- Durably sealed thanks to solid profile sealing
- See table for dimensions and weight
Connections for underground installation: we supply the tank as in the Graf Eco Plus package, with recesses where holes for piping need to be cut.
|Compare the Carat S Tank sizes|
|Tank||2700 Litres||3750 Litres||4800 Litres||6500 Litres|
|Weight||120 kg||150 kg||185 kg||220 kg|
|Half Height ie before assembly (for access)||700mm||790mm||910mm||1050mm|
|Go to other tank sizes||Go to a 2700L system||You are here||Go to a 4800L system||Go to a 6500L system|
- Download a technical drawing of the Carat 3750 litre tank by clicking here
- Watch video on assembly of Carat tank by clicking here
- A detailed catalogue on the Carat tank range can be downloaded by clicking here.
- Download a Carat tank installation guide by clicking here
- Otto Graf in Germany have a wealth of technical data and application illustrations on their website, including downloads and videos. To visit the Graf website please click here