5.4
Connecting the air hoses
The ventilation device and the three air lift pumps must be connected in the control box on the solenoid
valve side.
The hoses for the air lift pump must have a 13 mm inside diameter and the hose for the ventilation must
have a 19 mm inside diameter. When connecting the hoses it is important to be sure that they are joined
to the correct connections.
To prevent mistaking the connections, the air lift pumps and the downpipe of the ventilation into the tank
as well as the four connection points on the control box are colour coded as follows:
Feed lift pump (red)
Ventilation (
stainless steel)
Drainage lift pump (black)
Excess sludge lift pump (grey)
The connections must be joined according to their correct colours and then secured with hose clamps.
Hoses are also available in their appropriate colours.
After the hoses have been installed and connected, the empty conduit ends must be closed off to
prevent an exchange of gasses between the waste water facility and the environment of the
control box due to dampness, offensive odours and explosive gasses.
Here we recommend PU foam.
The hose surfaces and conduit walls should be cleaned with water and made damp with water before
filling with foam.
It is important to ensure that each hose is enclosed in foam from all sides. To make sure of a good
covering, the hoses should be moved backwards and forwards during the foam application.
Open internal switch cabinet with hose clips
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5. Assembly of the switch cabinet
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red hose, 13mm
blue hose, 19mm
black hose, 13mm
white hose, 13mm
Open external switch cabinet