Astoria 2GR - 6.5 Dispensing coffee

TECHNICIANS' manual
49 of 108
7.3.6 NON-RETURN DRAIN VALVE check
The non-return drain valve is an important component for
the correct operation of the machine. Perform the check as
follows:
• Activate the dispensing groups for about 30 seconds.
• Attachalterholder(7) with a pressure gauge (available
on request) to the dispensing group.
• Activate the dispensing group, and use the
pressure gauge (8) to monitor the pressure
as it increases up to 0.8-0.9 MPa (8-9 bar).
• Check that the pressure is increasing due to
the heated water expanding until it reaches
approximately 1.2 MPa (12 bar): when
this value is reached, it conrms that
the valve is working correctly and the
seals and solenoid valves are tight.
• Stop dispensing.
• Repeat the check on the other dispens-
ing groups.
If any malfunctions are de-
tected, the valve must be re-
placed.
7.4 Waterltermaintenance
7.4.1 Determining the water hardness
Aspart ofthe ltermaintenance,it isadvisable totest the
water beforehand.
To identify the carbonate hardness of the water use the spe-
cial kit as follows:
• Put 10 ml of water to be tested (1) in the test tube.
• Add a drop of reagent (2) and mix.
• Proceed in the same way by counting the number of drops
until the solution (3) turns from blue to red.
1 DROP = 1°dKH
Example: 9 Drops ----> 9°dKH carbonate hardness
3
1
2
7
8
7.4.2 Bypass conguration
Depending on the hardness of the water, adjust the bypass of
thewaterlterasshowninthetablebelow.Example:
9°dKH water hardness
Bypass adjustment 2
Water
hardness
(°dKH)
Bypass
Adjust.
Filter capacity (litres)
V M L XL
4 3 6.250 9.500 13.000 17.000
5 3 5.000 7.600 10.400 13.600
6 3 4.165 6.330 8.665 11.330
7 3 3.570 5.425 7.425 9.710
8 2 3.125 4.750 6.500 8.500
9 2 2.775 4.220 5.775 7.555
10 2 2.500 3.800 5.200 6.800
12 1 1.865 2.835 3.885 5.080
14 1 1.600 2.430 3.330 4.355
16 0 1.185 1.800 2.465 3.220
20 0 945 1.440 1.970 2.575
24 0 790 1.200 1.640 2.145
≥ 25 0 ≤ 755 ≤ 1,150 ≤ 1,575 ≤ 2.060
The values indicated in the table may vary, de-
pending on the type of lter cartridge used.
To adjust the bypass, push the (4) button and turn.
4