Midea MCCU-03CN1A, Installation Manual

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5
installation manual
CAUTION
Table 5-1
(mm)
Ø6.35/0.25in 8.3/0.327in 8.7/0.343in
Ø9.52/0.375in 12.0/0.472in 12.4/0.488in
Ø12.7/0.5in 15.4/0.606in 15.8/0.622in
Ø15.9/0.626in
Ø19.1/0.725in
18.6/0.732in 19.0/0.748in
22.9/0.902in 23.3/0.917in
R0.4~0.8
45 °±2
90 °
± 4
A
min max
Pipe gauge
Tightening torque
Flare dimensin A
Flare shape
97.2
～
118.6 N.m
(990
～
1210 kgf.cm)
(630
～
770 kgf.cm)
61.8
～
75.4 N.m
49.5
～
60.3 N.m
(504
～
616 kgf.cm)
32.7
～
39.9 N.m
(333
～
407 kgf.cm)
14.2
～
17.2 N.m
(144
～
176 kgf.cm)
Too large torque will harm the bellmouthing and too small will
cause leakage. Please determine the torque according to
Table 5-1.
Expel the air with a vacuum pump
3)
(Please refer to its manual for the way of using manifold
valve)
CAUTION
When the pumping has finished, close the Lo-lever of the
manifold valve completely and turn off the vacuum pump.
When you have pumped for over 15 minutes, please
confirm that the indicator of multimeter is on -1.0X10 -5 Pa
(-76cmHg)
Loosen and remove the nuts of service valves A and B to
open service valve A andB completely, then fasten nuts.
Disassemble the charge hose of service valve A, and
fasten the nut.
Both service valves should be open before test operation.
Each air conditioner has two service valves of different
sizes.(Refer to
Fig 5.4
)
Flare nut
Stopper
Cap
Valve body
Valve stern
5.2 Check the Leakage
Check all the joints with the leak detector or soap water.
( Refer Fig 5.5 as a reference illustration)
in the chart
A......Lo-stop valve
B......Hi-stop valve
C,D..Joints of the connecting pipe to the indoor unit.
B A
D C
Check-point of indoor unit
Check-point of outdoor unit
-76 cmHg
Lo-lever
Hi-lever
Charge hose
Charge hose
Vacuum pump
Lo-lever
Manifold valve
Multi-meter Pressure meter
Fig 5.3
Fig 5.4
Fig 5.5
Loosen and remove the nuts of service valves A and B,
and connect the charge hose of the manifold valve with
the maintenance terminator of service valve A. (Be sure
that service valves A and B are both closed)
Connect the joint of the charge hose with the vacuum
pump.
Open the Lo-lever of the manifold valve completely.
Turn on the vacuum pump. At the beginning of pumping,
loosen the nut of service valve B a little to check whether
the air comes in (the sound of the pump changes, and
the indicator of compound meter turns below zero). Then
fasten the nut.
5.3 Insulation
Be sure to completely insulate all the exposed parts of the flare
pipes.
Incomplete insulation may cause condensate.
In order to prevent faults caused by condensate of the
refrigerant pipe and drain pipe, perform condensate prevention
and heat insulation properly.
If it is forecast that high humidity/temperature environment
(condensate temperature is over 23
℃
) may exist in the ceiling,
e.g., inside the ceiling with slab, ceiling which is in the same
environment as the outdoor air), it is necessary to apply 10mm
or thicker adiabatic wool (16~20kg/m 2 ) to the refrigerant pipe
and the drain pipe in addition to applying the general heat
insulation materials. Enough heat insulation materials should
also be applied to the refrigerant joint and the pipe joint.
CAUTION
6. HEAT INSULATION OF THE PIPE
6.1 Heat Insulation Of The Pipe