Gaggia D90 Evolution Operating Instructions Manual

Also see for D90 Evolution: Specifications Use and maintenance

30ENGLISH6.2 PRESSURE SWITCH ADJUSTMENTThe pressure switch shown in the figure acts to keep theboiler pressure constant by engaging or de-activating the electricalheating resistance.This pressure switch is already calibrated to 1.1-1.3 bar during theinitial machine testing stage, but should a different working pressurebe required, it is possible to vary the operational field of the pressureswitch using the regulation screw (U); pressure reduction results ina reduction in temperature, whilst increasing the pressure will alsoincrease the water temperature.The regulation direction is shown in the figure and on the pressureswitch itself.The pressure varies by 0.1 atm for every complete screw turn,Warning: Disconnect the electricity supply beforeundertaking this operation.6.3 PUMP PRESSURE CALIBRATIONInsert the filter holder into the unit filled with regularly ground, dosedand pressed coffee.Switch on the unit switch (E90) (17) or the unit control keyboard(D90) (16) and read the pressure on the pump pressure gauge(11).NB: The correct pressure is of 8-9 atm.Should the pressure indicated on the pressure gauge be incorrect,turn it clockwise to increase the pump pressure and anti-clockwiseto reduce the pressure.Once adjustment is complete check pump calibration by deliveringone or more coffees.Z= Pump pressure adjustment screw.Warning !!When the machine is new the filter-holder sump may not bealigned (perpendicular to the machine itself) as shown inthe figure at the side, however this does not effect the efficientfunction of the same.After a short period of use the sump will gradually settle intoa correct position.A = Position of closed filter-holder with new machine.B = Position of closed filter holder with machine after a shortperiod of use.6.4 FILTERS FOR COFFEE MACHINEDepending on the quantity of coffee ground, the appropriate filtermust be as shown below to avoid that, once the coffee has drippedout, the leftover powder remains attached to the nozzle.IMPORTANT: N°2 under-tile packings with are thinner(8.1mm ) than that fitted as standard are included. Thesepackings may be used in the event of difficulty with insertionof the filter holder.NF08/002/B1 coffee cup of 5,5 gr. ÷ 6,5 gr.pod for 1 coffeebarley pod for 1 doseNF08/004/B1 coffee cup of 6 gr. ÷ 7 gr.NF08/005/B2 coffee cups of 12 gr. ÷ 14 gr.NF08/009/BDouble pod for 2 coffeesThe filter may be recognisedby the letter “C” printedinsideFig.6.03Fig.6.05Fig.6.04UZ20 mm24,5 mm24,5 mm21 mmFig.6.06A