Install the Biolet toilet

Check the temperature

The temperature must be at least 18°C to ensure it functions properly. The easiest thing to do is to fit a thermostatically controlled
radiator. If the toilet is not in use then the temperature need not be controlled, low temperatures will not damage the unit itself.


  • Air must escape via the pipe : In order to ensure adequate air supply, a vent (air opening) should be installed in the exterior wall. The exhaust air is evacuated through the toilet.
  • Access to air coming from inside: 25 m3 of air comes in the toilet room.  Make sure there is an opening, e.g. a free space of the toilet 
  • Avoid having an extra bathroom fan in the toilet room.  In a normal toilet, this is used to remove bad air.  As the air is already removed via the Biolet as it creates a back draught, which can lead to odours in the room.

How large is must the toilet room be ?

  • Biolet model 15, 25, 55 : 55 cm x 110 cm
  • Biolet model 65 : 65 cm x 135 cm
  • Separera 30 : 40 cm x 90 cm

Air Pipe inside and Outside difference

  • The air pipe evacuates the air.  All pipes going through the ceiling into cold spaces (e.g. the attic) must be insulated. This is to prevent draughts and condensation in the ventilation pipe. Insulation is essential, regardless of how much or how little the toilet is used.
  • Do not use pipe bends over 45° (we deliver bends of 45° or 35°).
  • Do not use a rain cap on top of the ventilation pipe - the air must be allowed to flow out freely.
  • Only the insect netting (part of standard delivery) should be on top of the pipe.

Possible installation Setups for Biolet models

Biolet Installation Scheme"

Installation via the wall kit

Biolet Composting toilet Installation with wall kit - tube via the wall

Installation : tube to the ceiling

Biolet composting toilet installation with tube