Mounting on the ceiling

Vallox 99 MV can now be equipped with an optional ceiling mounting plate. To attach the ceiling mounting plate:
  • On rafter frames or other frame structure with M8 thread bars so that they withstand the weight of the unit.
  • Ensure that the installation plate is horizontally level, as this determines the position of the unit.
  • The top edge of the white covering strip of the ceiling mounting plate can be installed against the ceiling. Alternatively, a concealed mounting method can be used, in which case the ceiling can be 30 mm below the top of the white covering strip.

Insulate the ducts against condensation also between the unit and the ceiling mounting plate.

Note: When installing the unit, reserve a space of at least 500 mm in front of the unit for servicing purposes.
Note: Mount the ventilation unit in a place where the temperature does not fall below +10°C.


  1. Attach the ceiling mounting plate:
    1. Fasten the thread bars on the rafter frames or other frame structure, and screw the nuts (E) onto the bars.
    2. Lift the ceiling mounting plate in place.
    3. Push a rubber damper (F) and a washer (G) to each thread bar.
    4. Adjust the nuts so that the ceiling mounting plate is level.
    5. Shorten the lower ends of the thread bars so that they are no more than 5 mm below the nuts.
    Warning: The ventilation unit is very heavy. Do not perform this procedure alone.
  2. Install the ventilation unit on the ceiling mounting plate:
    1. Install the ceiling mounting plate with M8 thread bars so that it is horizontally level.
      Note: The end of the thread bars must be 5 mm or less below the fastening nut. Do not fasten the ceiling mounting plate too tight to the ceiling. Ensure that the sliding bars move and restore to their original position by pulling from the operating levers (A).
      The top edge of the white covering strip of the ceiling mounting plate can be installed against the ceiling. Alternatively, a concealed mounting method can be used, in which case the ceiling can be 30 mm below the top of the white covering strip.
    2. Ensure that the insulation washers are in the outlet collars below the ceiling mounting plate.
    3. Remove the door before installing the ventilation unit to the ceiling mounting plate.
    4. Lift the ventilation unit close to the ceiling mounting plate and feed the cables and the connection box through the hole in the ceiling mounting plate on top of the ceiling.
      Note: Remember to make a service door in the ceiling so that the cables and the connection box can be accessed. The distance between the service door and the ceiling mounting plate must be around 500 mm.
      Alternatively, the cables can be fed to the rear wall between the ceiling mounting plate and the ventilation unit. When the ventilation unit is lifted against the ceiling mounting plate, the unit locks in place. Where needed, guide the mounting hooks on the ceiling mounting plate (B) to the grooves on the side panels of the ventilation unit.
      There are operating levers (A) on the front bottom corners of the ceiling mounting plate. When the levers have been restored to the same level with the white covering strip of the ceiling mounting plate, the unit has been locked in place.
    5. Where required, the unit can be detached from the ceiling mounting plate. Remove the door of the unit. Lift the unit slightly upwards and pull simultaneously from both operating levers (A) of the ceiling mounting plate to detach the unit from the ceiling mounting plate.

Attic floor penetration plate

The attic floor penetration plate (D) is optional. When an attic floor penetration plate is used, the tightness of the vapour barrier has to be ensured.

The attic floor penetration plate can be fastened on the finished rear wall. The minimum distance of the attic floor penetration plate from the finished side walls is 15 mm.