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Air admittance valve HL 903 is designed for installation in unventilated sewer risers. The valve protects sanitary devices against disruption of water trap and the room against polluted air. It can be installed on risers with diameters of 32, 40 and 50 mm. Capacity is 8 l/s. You can mount this air admittance valve on a long horizontal pipe, but pipe length must be greater 4 meters.
| Diameter | Material | Capacity | Weight |
|---|---|---|---|
| DN, mm | l/s | gr | |
| 32 40 50 |
ABS/ polypropylene |
8 | 139 |
Download data sheet: 
Air admittance valve HL 903
Download example of product installation: 
Air admittance valve HL 903
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Hutterer & Lechner Gasket wedge shaped, DN40 [Code number: HL 01008D]
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Hutterer & Lechner Locking nut, 6/4" [Code number: HL 01047D]
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Hutterer & Lechner adapter for HL904, DN32/40/50 [Code number: HL 0904.0E]
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