38
COSMOGAS
Ecotwin
6.16.2 - Checking the tightness of the
refrigerant circuit
Refer to Figure 6-19:
1.- Remove the cap “D” and connect a nitrogen bottle equipped
with a pressure regulator to the charge connection of the
outdoor unit “C”;
2.- Progressively fill the circuit with nitrogen, in 5 bar
increments, by acting on the pressure regulator until
reaching 40 bar;
3.- Check the tightness of the fittings with a leak detector
spray. If there are leaks, repeat the operations of points 2,
3 and 4 of section 6.16.1 and check the tightness again;
4.- Release the pressure and nitrogen;
5.- Proceed with the evacuation of the air from the refrigerat
circuit and release of the refrigerant as per section 6.16.3.
6.16.3 - Evacuation of the air from
the refrigerant circuit and release the
refrigerant
1. - Connect a vacuum pump “E” (Figure 6-19) with a minimum
flow rate of 4 m3 / h to the fitting on the outdoor unit (detail
“C” of Figures 6-19 and 6-20). Furthermore, connect in
parallel a vacuum gauge “F” (Figure 6-19) to check the
residual pressure reached;
2.- Turn on the vacuum pump and let it act for about an hour.
Check that the vacuum degree reached is less than 0.5
mbar;
3.- Close the vacuum pump valve and check that the residual
pressure on the vacuum gauge does not increase;
4.- Close the vacuum gauge tap to avoid damage to the
instrument;
5.- After stopping the vacuum pump, remove the cap “A”
(Figure 6-20) and immediately open the internal valve “B”
(Figure 6-20) using an allen key;
WARNING!!! Once the valves have been unscrewed
and reached the limit switch (fully open), screw them back
about 3/4 of a turn to ensure the tightness of the internal
O-rings.
6.- Reposition the cap “A” on the fitting “B” (Figure 6-20);
7.- Disconnect the vacuum gauge and the vacuum pump;
8.- Reposition the cap “D” on the fitting “C” (Figure 6-20);
9.- Tighten the caps “A” and “D” (Figure 6-20) with the aid
of a torque wrench (tightening torque from 20 to 25 Nm);
10.- Check the tightness of the fittings using a leak detector;
11.- Add refrigerant according to the length of the refrigerant
circuit, as reported in section 6.16.4.
6 - INSTALLATION
C
B
D
A
62403796.01.007
Figure 6-20 - Outdoor unit connection
LEGEND of Figure 6-20:
A - Cap
B - Internal valve
C - Connection for the vacuum pump
D - Vacuum pump connection cap
