25
INSTALLATION
9
Carefully check for absence of leakages from the closing
point of the plug.
Circuit tightness check
The appliance is tested at the factory and the indoor refrigerat-
ing circuit tightness does not usually need to be checked.
The refrigerating circuit built on site needs to be checked instead.
To check tightness:
—
keep the outdoor unit shut-off valves closed
A
High pressure
B
Low pressure
1
Pressure regulator
2
Nitrogen cylinder
3
Pressure gauge unit
4
3-way valve service connection
N2
A
B
1
2
3
4
1
3-way valve service connection
1
—
charge the circuit with nitrogen through the service con-
nection on the 3-way shut-off valve
0
Do not use oxygen or acetylene or other flammable or poi-
sonous gases in the refrigerating circuit, as they can cause
explosions.
—
reach a pressure equal to 0.3 Mpa
—
wait 3 minutes.
—
check that the pressure has not dropped
—
reach a pressure equal to 1.5 Mpa
—
wait 3 minutes.
—
check that the pressure has not dropped
—
reach a pressure equal to 3 Mpa
—
adjust the reached pressure and room temperature
—
leave the circuit pressurised for 1 day
—
check that the pressure has not dropped
9
If the temperature has changed with respect to the noted
value consider that the pressure varied by 0.01 Mpa for 1 °C.
9
If pressure has dropped, detect the leak, fix it and repeat
the test.
9
To detect the leak, use a solution of water and soap and
check all the joints and welds, if any.
Having verified the absence of leakages:
—
create a pneumatic vacuum inside the circuit
Pneumatic vacuum
To create vacuum in the circuit:
—
keep the outdoor unit shut-off valves closed
A
High pressure
B
Low pressure
1
Pressure gauge unit
2
Vacuum pump
3
3-way valve service connection
A
B
1
2
3
—
connect the vacuum pump to the pressure gauge unit
—
connect the pressure gauge unit to the service connection
on the 3-way shut-off valve
—
completely close the pressure reducing valve of the pres-
sure gauge
—
fully open the low pressure valve of the pressure gauge unit
—
let the vacuum pump work for at least 15 minutes
—
reach a pressure that is close to -0.1 Mpa
—
close the low pressure valve of the pressure gauge unit
—
switch off the vacuum pump
—
wait 5 minutes
—
check that the pressure has not risen again
Содержание AARIA MULTI 250 P
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