Unit Function HDS Middle Range / HDS Premium RangePage 56 / 127 Service Manual 04.20082.25 Functional diagram, suction feed operation1 Cleaning agent tank 12 Cleaning agent suction hose with filter3 Level sensor, cleaning agent tank 1(optional)4 Cleaning agent suction hose with filter5 Level sensor, cleaning agent tank 2(optional)6 Cleaning agent tank 27 Suction hose with filter and non-returnvalve (optional)8 Open tank9 Cleaning agent solenoid valve 2 (optional)10 Cleaning agent solenoid valve 1 (optional)11 Cleaning agent metering valve12 Cleaning agent suction hose13 Cleaning agent non-return valve14 Pressure switch, „ON“15 Pressure and flow control valve16 Oil reservoir19 Fuel filter20 Fuel tank21 Level sensor, fuel tank22 Fuel suction line23 Fuel return line24 Fuel pump25 Solenoid valve, fuel pump26 Continuous-flow heater27 Fuel pressure line28 Ignition electrodes29 Fuel nozzle30 Exhaust connecting sleeve31 Exhaust temperature sensor32 Adjustment, water temperature33 Printed circuit board34 Temperature sensor35 Heating coil, continuous flow heater36 Air flap, air volume adjustment37 Fine water filter38 Burner fan39 Motor housing with cooling coil (in water-cooled motor only)40 Pressure switch, „OFF“41 Safety block with low-water protectionand safety valve42 Pressure gauge43 Pressure pipe44 Solenoid valve, scale inhibitor45 Level sensor, scale inhibitor tank46 Scale inhibitor tank47 Float valve48 Float tank49 High-pressure nozzle50 Spray lance51 Softgrip easy-press handgun52 High-pressure hose53 Rotary control for pressure and flowcontrol valve54 Rinsing line55 Plug for closing off the rinsing line duringsuction operation56 Hose from float tank to the pump head57 Hose from the motor cooler to the finewater filter/pump headNoteDuring suction operation the float tank Item48 must be bypassed.Procedure:– Remove hose (56) at the pump head.– Remove hose (57) from the fine waterfilter.– Connect hose (57) to the pump head.– Pull rinsing line off the suction tube andpush onto plug (55).