HDS Middle Range / HDS Premium Range Basic Settings and Service ProceduresService Manual 04.2008 Page 95 / 1271234561 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 maximum operating pressure– Install test pressure gauge (special tool) athigh-pressure connection. The high-pressureconnection can be directly at the unit outlet oron the handgun in units with hose reel.– Connect the high-pressure hose with handgunand rotary control to the test pressure gauge.– Twist in the rotating handle of the pressureand flow control valve at the pump up to thelimit stop („+“ direction).– Turn rotary control to position for lowestpressure at the nozzle („-“ direction), openhandgun and let unit run.– Then pull off the rotating handle.– Undo the lock nut (2) for high-pressureadjusting screw (1).– Turn the high-pressure adjusting screw (1) sothat the opening pressure from the overflowvalve (see Technical Specifications, full load)at the test pressure gauge is reached.– After adjusting, secure the high-pressureadjusting screw (1) with the lock nut (2). Re-check operating pressure, flow rate andswitching points of the pressure switch.– Finally, seal the high-pressure adjustmentscrew (1) and the lock nut (2) with lockingcompound.Note:Turn in clockwise direction to increase thepressure, turn in anti-clockwise direction toreduce the pressure.3.5 Adjusting the operating pressure using the rotary control onthe handgunNote:The opening pressure of the overflow valveis adjusted using the rotary control.
