Basic Settings and Service Procedures HDS Middle Range / HDS Premium RangePage 96 / 127 Service Manual 04.20081234561 Adjusting screw, high pressure2 Lock nut, high pressure adjusting screw3 Spindle, pressure and flow control valve4 Adjusting screw, low pressure5 Lock nut, low pressure adjusting screw6 Housing, unloader valveAdjusting the minimum operating pressure– Install test pressure gauge at high-pressureconnection.– Connect the high-pressure hose with handgunand rotary control to the test pressure gauge.– Install the new high-pressure nozzle.– Rotary control completely open (turn in „+“direction), open handgun and let unit run.– Unscrew the rotating handle of the pressureand flow control valve at the pump up to thelimit stop („-“ direction).– Then pull off the rotating handle.– Loosen the lock nut (5).– Twist the low-pressure adjusting screw (4)and spindle (3) together until the minimumoperating pressure (see TechnicalNote:Turn in clockwise direction to increase thepressure, turn in anti-clockwise direction toreduce the pressure.Specifications, part load) is reached at the testpressure gauge.– After adjusting, secure the low-pressureadjusting screw (4) with the lock nut (5). Re-check operating pressure, flow rate andswitching points of the pressure switch.– Finally, seal the low-pressure adjustmentscrew (4) and the lock nut (5) with lockingcompound.3.5 Adjusting the operating pressure using the rotary control onthe handgunNote:At minimum pressure and flow setting andif using the steam nozzle supplied, thepressure may not exceed 32 bar.
