Mitsubishi Electric MXZ-3B24NA Notice D'installation page 6

3. FLARING WORK AND PIPE CONNECTION
3-1. FLARING WORK
1) Cut the copper pipe correctly with pipe cutter. (Fig. 1, 2)
2) Completely remove all burrs from the cut cross section Good No good
of pipe. (Fig. 3) Copper a ' , \
* Aim the copper pipe downward while removing burrs (<< pipe Th cl mm Burr Copper pipe
to prevent burrs from dropping in the pipe. 2 EA He Z Spare reamer
3) Remove flare nuts attached to indoor and outdoor units, oo . ° ' me a /&—Pipe cutter l
then put them on pipe having completed burr removal. Tilted Uneven Burred | |
(Not possible to put them on after flaring work.) Fig. 4 Fig. 2 Fig. 3
4) Flaring work (Fig. 4, 5). Firmly hold copper pipe in the
dimension shown in the table. Select A mm from the Flaring tool A Inside is shin-
table according to the tool selected. Smooth all ing without any
5) Check s around \, scratches.
* Compare the flared work with Fig. 6. \ / OS i?
° If flare is noted to be defective, cut off the flared sec- Die / ik Copper pipe BA
tion and do flaring work again. . [ oS Even length
Clutch type Wing nut type Flare nut 1
Fig. 4 Fig. 5 Fig. 6
Pipe diameter Nut A[mm (inch)] Tightening torque
[mm (inch)] (mm) | Clutch type tool for R410A} Clutch type tool for R22_ | Wing nut type tool for R22 Nem kgfecm ftelb
26.35 (1/4) 17 1.5 to 2.0 13.7 to 17.7 140 to 180 10 to 13
29.52 (3/8) 22 0 to 0.5 1.0 to 1.5 (0.06 to 0.08) 34.3 to 41.2 350 to 420 25 to 30
012.7 (1/2) 26 (0 to 0.02) (0.04 to 0.06) 2.0 to 2.5 49.0 to 56.4 500 to 575 36 to 42
015.88 (5/8) 29 (0.08 to 1.0) 73.5 to 78.4 750 to 800 54 to 58
3-2. PIPE CONNECTION
1) Apply a thin coat of refrigeration oil (G) to the flared ends of the pipes and
the pipe connections of the outdoor unit.
2) Align the center of the pipe with that of the pipe connections of the outdoor
unit, then hand tighten the flare nut 3 to 4 turns.
3) Tighten the flare nut with a torque wrench as specified in the table. A WARNING
* Over-tightening may cause damage to the flare nut, resulting in refriger- When installing the unit, securely
ant leakage. / / / ; connect the refrigerant pipes before
* Be sure to wrap insulation around the piping. Direct contact with the bare starting the compressor.
piping may result in burns or frostbite.
3-3. INSULATION AND TAPING
1) Cover piping joints with pipe cover.
2) For outdoor unit side, surely insulate every piping including valves. A CAUTION
3) Using piping tape (E), apply taping starting from the entry of outdoor unit. 7
* Stop the end of piping tape (E) with tape (with adhesive agent attached). When there are the ports which are
* When piping have to be arranged through above ceiling, closet or where not used, make sure their nuts are
the temperature and humidity are high, wind additional commercially sold tightened securely.
insulation to prevent condensation.
4. PURGING PROCEDURES, LEAK TEST, AND TEST RUN
4-1. PURGING PROCEDURES AND LEAK TEST
1) Remove service port cap of stop valve on the side of the outdoor unit gas ~0.101MPa
pipe. (The stop valves are fully closed and covered in caps in their initial [-760 mmHg Compound pressure
state.) "4 to 5 turns Stop valve cap (-30 in. Hg)} Gauge (For R410A)
2) Connect gauge manifold valve and vacuum pump to service port of stop . (Torque 19.6 to 29.4 Nem,
valve on the gas pipe side of the outdoor unit. Close Bt) kgfrom, 15 to
3) Run the vacuum pump. (Vacuumize for more than 15 minutes.)
4) Check the vacuum with gauge manifold valve, then close gauge manifold
valve, and stop the vacuum pump.
Pressure gauge
# (for R410A)
Gauge manifold
Stop valve valve (for R410A)}
for GAS
ae A . Handle High
5) Leave as it is for one or two minutes. Make sure the pointer of gauge Hexagonal wrench
manifold valve remains in the same position. Confirm that pressure gauge GreiOny
shows -0.101 MPa [Gauge] (~760 mmHg) (-30 in. Hg).
6) Remove gauge manifold valve quickly from service port of stop valve. Service port cap
(Torque 13.7 to
7) Fully open all stop valves on the gas pipe and the liquid pipe. Operating 17.7 Nem, 140 to why
without fully opening lowers the performance and this causes trouble. 180 kgfecm, 10 to
8) Refer to 1-2., and charge the prescribed amount of refrigerant if needed. 13 ftelb) Vacuum pump
top valve {for R410A)
Be sure to charge slowly with liquid refrigerant. Otherwise, composition of
for LIQUID
the refrigerant in the system may be changed and affect performance of
the air conditioner. :
9) Tighten cap of service port to obtain the initial status. Precautions when using When attaching the control valve to
10)Leak test the control valve the service port, valve core may de-
form or loosen ifexcess pressure is
applied. This may cause gas leak,
Service port When attaching the control valve to
the service port, make sure that the
valve core is in closed position, and
then tighten part A. Do not tighten
Charge hose Part A or turn the body when valve
Body (for R410A) Core is in open position.
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