Basic Settings and Service Procedures HDS Middle Range / HDS Premium RangePage 98 / 127 Service Manual 04.20083.6 Adjusting the operating pressure using standard handgunwithout rotary control1234561 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 standardhandgun at the test pressure gauge.– Install the new high-pressure nozzle.– Open standard handgun and let the 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 TechnicalSpecifications, part load) is reached at the testpressure gauge.Note:Turn in clockwise direction to increase thepressure, turn in anti-clockwise direction toreduce the pressure.– 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.Note:At minimum pressure and flow setting andif using the steam nozzle supplied, thepressure may not exceed 32 bar.
