HDS Middle Range / HDS Premium Range Basic Settings and Service ProceduresService Manual 04.2008 Page 93 / 1273.3 Burner settingFuel pump, fuel pressure adjustmentAir flap, air volume adjustment1 Pressure line to the burner2 Fuel pump3 Adjusting screw, fuel pressure4 Suction hose, fuel5 Return hose to the fuel tank6 Air flap, air volume adjustment7 Locking screw, air flap1425367Measuring the water temperature– Install shut-off valve with thermometer (specialtool) in the unit outlet.– Switch on burner and bring unit with shut-offvalve to operating pressure at full water volume.– Let unit run in burner operation for approx. 5minutes until the maximum water temperatureis reached.– Determine increase in water temperature(water outlet temperature minus water inlettemperature).– For nominal value, see „TechnicalSpecifications“– Measure smoke number, CO 2 level andexhaust temperature (special measuringequipment tool).Note:Precise basic setting of the burner is onlypossible if the heating coil has beenthoroughly cleaned of soot and the innerdeposits have been removed beforehand.Adjusting the fuel pressure– Adjust fuel pressure (and water temperature)using adjusting screw (3) (see arrow).– For nominal value, see „TechnicalSpecifications“Adjusting the smoke number– If the smoke number is too high the air flap (6)must be opened further or the fuel pressuremust be reduced.Adjust CO 2 value– Adjust CO2 value by adjusting the air flap (seearrow). Open air flap, CO 2 level reduces.Note:After completing the basic setting, seal thefuel pump and air flap.
