Midea MCA3I-09FNXD0 Owner's Manual page 35

Step 2: Remove burrs.
Burrs can a ect the air-tight seal of refrigerant
piping connection. They must be completely
removed.
1. Hold the pipe at a downward angle to
prevent burrs from falling into the pipe.
2. Using a reamer or deburring tool, remove
all burrs from the cut section of the pipe.
Point down
Fig. 7.4
Step 3: Flare pipe ends
Proper flaring is essential to achieve an airtight
seal.
1. After removing burrs from cut pipe, seal
the ends with PVC tape to prevent foreign
materials from entering the pipe.
2. Sheath the pipe with insulating material.
3. Place flare nuts on both ends of pipe.
Make sure they are facing in the right
direction, because you can't put them on
or change their direction after flaring.
See Fig. 7.5
Flare nut
Copper pipe
Fig. 7.5
4. Remove PVC tape from ends of pipe when
ready to perform flaring work.
5. Clamp flare form on the end of the pipe.
The end of the pipe must extend beyond
the flare form.
Flare form
Fig. 7.6
 Page 18 
Pipe
Reamer
Pipe
6. Place flaring tool onto the form.
7. Turn the handle of the flaring tool
clockwise until the pipe is fully flared. Flare
the pipe in accordance with the dimensions
shown in table 7.3.
Table 7.3: PIPING EXTENSION BEYOND FLARE
FORM
Pipe Tightening Flare dimension (A)
torque (Unit: mm/Inch)
gauge
Min.
18-20N.m
Ø 6.4 8.4/0.33
(183-204kgf.cm)
25-26 N.m
Ø 9.5 13.2/0.52
(255-265 kgf.cm)
35-36 N.m
Ø 12.7 16.2/0.64
(357-367 kgf.cm)
45-47 N.m
Ø 15.9 19.2/0.76
(459-480 kgf.cm)
8. Remove the flaring tool and flare form,
then inspect the end of the pipe for cracks
and even flaring.
Step 4: Connect pipes
Connect the copper pipes to the indoor unit first,
then connect it to the outdoor unit. You should
first connect the low-pressure pipe, then the
high-pressure pipe.
1. When connecting the flare nuts, apply a
thin coat of refrigeration oil to the flared
ends of the pipes.
2. Align the center of the two pipes that you
will connect.
Indoor unit tubing
Fig. 7.8
3. Tighten the flare nut as tightly as possible
by hand.
4. Using a spanner, grip the nut on the unit
tubing.
5. While firmly gripping the nut, use a torque
wrench to tighten the flare nut according
to the torque values in table 7.3.
NOTE: Use both a spanner and a torque wrench
when connecting or disconnecting pipes to/from
the unit.
Flare shape
Max .
90 ° ± 4
8.7/0.34
A
13.5/0.53
R0.4~0.8
16.5/0.65
19.7/0.78 Fig. 7.7
Pipe
Flare nut
Fig. 7.9