Is the lever in correct position?
Foaming: position for foaming (white)
Rinsing: position for water (blue)
Disinfection: position for disinfection (red, only RFD)
Is there sufficient agent in the jerrycan?
Check jerry can.
Is the suction hose immersed far enough into the liquid?
Check the position of the hose.
Is compressed air present when foaming?
Check the compressed air line.
Is the correct lance and nozzle mounted?
Rinsing: blue lance
Foaming: with lance