17OPERATING INSTRUCTIONS• after around 30 minutes, when the light comes on (section 12 -point 1), turn the steam knob half a turn clockwise (Fig.6) until itstops.The machine must be rinsed so as to eliminate the residues of descalingsolution from inside the machine. Proceed as follows:• remove the water tank, rinse it and fill it with clean water.• reposition the tank.• empty the collection container (located under the milk frother) that isfull of liquid, and then replace it under the milk frother.• turn the steam knob half a turn counter-clockwise (Fig. 5). Hot waterwill come out of the milk frother and fill the container underneath.• when the tank is empty, the l ight goes off and the lightcomes on (section 12 - point 1).• turn the steam knob all the way clockwise (Fig. 6) and fill the watertank with clean water again.• the program of descaling is now terminated and the machine isready to make coffee again.NOTE: if the descaling procedure is interrupted before completion,the alarm (section 12 - point 5) is not deactivated and the pro-cedure must be started again form the beginning.IMPORTANT: FAILURE TO DESCALE THE APPLIANCE REGULARLY INVALIDATESTHE WARRANTY.10.4 SETTING THE WATER HARDNESSThe light (section 12 - point 5) switches on after after the machine hasbeen operated for a factory set period of time calculated on the basis of themaximum quantity of lime scale which may be contained in the water used. Ifnecessary, this period of operation can be extended, thus making the descal-ing operation less frequent, by programming the machine based on the actuallime content in the water used. Proceed as follows:• after having removed the "Total hardness test" strip (enclosed on page 2)from its packaging, dip it fully in the water for a few seconds, then pull itout and wait around 30 seconds (until it changes color anda number ofsquares are formed);• check that the machine is off (all the indicator lights are off);• press the button (Fig. 14) and hold it for at least 5 seconds. The fourlights , , and come on.• press the button (Fig.18) repeatedly until the number of lights that areon coincides with the number of red squares on the test strip (for example,if there are 3 red squares on the test strip, press the button until 3 indi-cator lights come on together, , and ).• press the button (Fig. 14) to save the data. The coffee maker is nowprogrammed to provide the descaling warning when effectively necessary,based on the actual hardness of the water.