Go to Studor
Hong Kong
Puerto Rico
United States
South Korea
New Zealand
United Kingdom


Studor® Maxi-Filtra™

A Practical Two-way Vent for External Drainage Systems

The Studor Maxi-Filtra is a very sturdy filter designed specifically for outdoor applications to eliminate bad odours. Its robust design means the Maxi-Filtra can be used vertically or horizontally and can be installed in hard-to-reach places.

The active carbon filter operates as a two-way vent, filtering air in both directions and is packaged in a very resilient exterior for longevity, with a replaceable filter.

Particularly used on the ventilation pipe of septic tanks, the Maxi-Filtra may be installed when the odour from existing vents is a problem, or when vents are to be included in the drainage system of a new build.

Other installation locations may include water tanks and silos, where an active carbon vent is required to prevent a vacuum. Here an airflow rate of up to 5 litres per second can be accommodated with a 100mm diameter pipe.

Pressure (Pa)
Flow Rate (l/s)
100 2
250 5
500 8

For best results, the Maxi-Filtra should always be installed in conjunction with Studor Air Admittance Valves (AAVs) throughout the drainage system and we recommend that the filter should be replaced at least every two years.

Maxi-Filtra installation
Maxi-Filtra Installation

Occasionally, to eliminate the bad odours from drainage vent stacks, a Maxi-Filtra can also be used.

To ensure the correct function of the drainage system (subject to local regulations) we recommend that the Maxi-Filtra is fitted in conjunction with a Maxi-Vent. See below for an example of this type of installation.

Maxi-Filtra installation
Maxi-Filtra Installation

Maintenance and Ease of Installation

No specialist installation is required for this type of filter. The Maxi-Filtra is commonly installed with a push-fit connector only, so you don’t even need to be skilled to secure the filter in place. The cap simply lifts off to enable easy access for filter cartridge replacement. In installations with high odour saturation, the carbon filter should be replaced more regularly than our recommended two years, or when odour becomes noticeable.

The Maxi-Filtra, supplied with one carbon filter and the connector as standard, fits 90mm venting pipes without the connector and 75mm/110mm with the connector. The Aluminium Cover provides protection for the Maxi-Filtra when it is installed outside in the open air. This gives added insulation against extreme temperatures (-20°C to +60°C) and protection from animal/birds and the environment, i.e. inclement weather and the sun's ultra-violet rays.

Please contact the Studor team if you have special requirements or applications, such as lifting equipment, grease separators or STP (sewer treatment plants).

For further details please refer to the links on this page or contact the distributor in your country who will assist you with your questions or advise you of how to place an order.