Internal XL filters

New: DN 150 connection for Graf underground tanks from 8,500 l

Graf, the market leader in Europe for rainwater harvesting products, is fitting its underground rainwater tank Carat (from 8,500 l capacity) with DIN 150 connections. In other words, the one filter integrated in the tank dome can now drain roof areas of up to 750 m2 in size, e.g. for residential complexes or commercial buildings. This saves space and cuts installation costs.

For its underground rainwater tanks Carat XL and XXL, Graf offers the integrated filter solutions Universal-Filter 3 XL Internal (for roof areas of up to 500m2) and Optimax-Pro Filter XL Intern (for roof areas of up to 750m2). Thanks to their compact size and the small difference between their inlet and outlet heights, these filters can be fitted to a DN 150 connection directly in to the tank dome. Therefore, there is no need for an external filter shaft, helping to cut the installation work and costs dramatically. Moreover, the integrated filter solution conceals additional covers.

Optimax-Pro Filter XL: Self-cleaning filter insert

The new Graf Optimax-Pro Filter XL Internal can quickly filter the water draining off large roof areas even from heavy rainfalls. The patented filter technology achieves a high efficiency exceeding 95% even in heavy rain. The Optimax-Pro Filter XL Internal filters the water through a self-cleaning stainless steel filter insert with a mesh width of 0.35 mm. This self-cleaning design reduces the maintenance work and costs greatly.

The housing is fitted with a transparent cover for ease of filter inspections. The filter’s operations can therefore be inspected without the need to remove the filter insert. The filter insert can be fitted with the optional 50 cm Plus removal handle for ease of removal even from greater installation depths. Just a few simple manual steps are needed to remove the filter housing for tank inspections, without any tools.

The filter is also offered with an optional patented cleaning unit for even longer maintenance intervals. A powerful water jet cleans the filter screen, thereby extending the maintenance intervals for the filter area. Dirt is then flushed into the tank overflow. This process can take place either manually or fully automatically when the Graf controllers are installed.

Universal-Filter 3 XL: 100% water yield

Thanks to its filter basket, the Graf Universal-Filter 3 XL Internal attains a water yield of 100%. Its filter insert also presents a mesh width of 0.35 mm. For cleaning, the basket features a practical lifting device for easy removal. The Universal-Filter 3 XL Intern is also fitted with a sealed housing including emergency overflow that prevents the filter basket from spilling its contents into the tank.

In future, the new filter systems will also be included in the tried and tested Graf complete packages.


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Hanna Kreutz

Hanna Kreutz
+49 (0) 76 41/ 589 - 984

kreutz@graf.info

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