Pumpfix S Underfloor basement drain

Stronger than the backwater: The Pumpfix S Underfloor is the only basement drain with a backwater valve that pumps against backwater. It normally disposes of wastewater without sewage continuously via the free slope to the sewer – even in the event of a burst water pipe or flooding. Yet it shows its true strength in the event of backwater: The pump then switches on automatically and the Pumpfix S Underfloor drains reliably, even against the backwater pressure. It is also ideally suited for draining outdoor basement stairs.

The Pumpfix S Underfloor is available in two versions: a compact version with a polymer cover, which is particularly suitable for renovation projects, and a larger version with numerous connection options and a tileable surface.

The Pumpfix S Underfloor basement drain normally uses the natural slope to the sewer. The continuous disposal of wastewater is also possible in the event of a burst water pipe or flooding. In the event of backwater, the pump switches on automatically and drains reliably, even against the backwater pressure.

In addition to the inlet option via the cover, several horizontal inlets can also be attached, for example, for a shower, washing machine and washbasin (Drilling open the drain body allows connections of up to DN 100 to be fitted, above the compression flange and in the upper section up to DN 70). The Pumpfix S Underfloor basement drain can therefore also be used as central backwater protection.

The KESSEL sealing set for installation in waterproof concrete ensures reliable protection against ground water. The extension section with a central flange and elastomeric waterproofing membrane enable implementation also in deeper installation situations.

The radioactive noble gas radon is a natural element that is present virtually everywhere in our earth's crust. If it accumulates in a high concentration within enclosed spaces, it can be hazardous to humans: Radon is considered an environmental risk factor for lung cancer. The Pumpfix S Underfloor for floor slab installation helps to prevent this health hazard from entering buildings. The backwater valve has been tested and certified as radon-proof.

Features & benefits

Automatic pump activation during backwater events — drains even against backwater pressure
Dual-mode operation: gravity flow under normal conditions, pumped drainage during backwater
Handles continuous wastewater disposal even in the event of a burst water pipe or flooding
Suitable for draining outdoor basement stairs
Multiple horizontal inlet connection options (shower, washing machine, washbasin)
Drill-open drain body allows connections up to DN 100 (above compression flange) and up to DN 70 in upper section
Can be used as central backwater protection for multiple drainage points
Available in two versions: compact polymer cover (ideal for renovations) and tileable cover with numerous connection options
Compatible with waterproof concrete installation via KESSEL sealing set
Extension section with central flange and elastomeric waterproofing membrane for deeper installation situations
Backwater valve tested and certified as radon-proof
GTF 500 pump with documented performance curve

Applications

Basement floor slab installation
Outdoor basement stair drainage
Central backwater protection for multiple drainage points (shower, washing machine, washbasin)
Renovation projects (compact version with polymer cover)
Waterproof concrete installations
Properties at risk of backwater or flooding

Technical specifications

Pump model	GTF 500
Nominal size (DN)	DN 100
Installation depth	330 mm
Length	485 mm
Width	380 mm
Backwater protection type	Type 5
Max connection size (drain body)	DN 100
Max connection size (upper section)	DN 70
Available cover types	Cover plate; Tileable cover plate
Radon-proof certification	Yes — tested and certified