Purging Procedures, Leak Test, And Test Run - Mitsubishi Electric MSZ-D30NA Manuel D'installation

A inch (mm)
B
Pipe diameter
Clutch
inch
inch (mm)
type tool
(mm)
for R410A
21/32
ø 1/4 (6.35)
(17)
ø 3/8 (9.52) 7/8 (22)
0 to 0.02 0.04 to 0.06
(0 to 0.5) (1.0 to 1.5)
1-1/32
ø 1/2 (12.7)
(26)
1-5/32
ø 5/8 (15.88)
(29)
3-2. FLARE CONNECTION
1) Cut the copper pipe as straight as possible with a pipe cutter. (Fig. 1, 2)
2) Remove all burrs from the cut section of the pipe, ensuring that precautions are taken to
avoid getting metal shavings into the piping. (Fig. 3)
3) Remove flare nuts attached to indoor and outdoor units, then put them on pipe.
4) Flaring work (Fig. 4, 5). Firmly hold copper pipe in the dimension shown in the table.
Select A inch (mm) from the table according to the tool you use.
5) Check
• Compare the flared work with Fig. 6.
• If flare is defective, cut off the section and repeat procedure.
3-3. PIPE CONNECTION
• Fasten flare nut with a torque wrench as specified in the table above.
• When fastened too tight, flare nut may eventually break and cause refrigerant leakage.
• Be sure to wrap insulation around the piping. Direct contact with the bare piping may
result in burns or frostbite.
Indoor unit connection
Connect both liquid and gas piping to indoor unit.
• Apply a thin coat of refrigeration oil (J) on the flared ends of the pipes. Do not apply
refrigeration oil on screw threads. Excessive tightening torque will result in damage on
the screw.
• To connect, first align the center, then tighten the first 3 to 4 turns of flare nut.
• Use tightening torque table above as a guideline for indoor unit side joints, and tighten
using two wrenches. Excessive tightening damages the flare section.
Outdoor unit connection
Connect pipes to stop valve pipe joint of the outdoor unit following the same procedure
detailed in Indoor unit connection.
• For tightening, use a torque wrench or spanner.
When installing the unit, securely connect the refrigerant pipes before starting the
compressor.
3-4. INSULATION AND TAPING
1) Cover piping joints with pipe cover.
2) For outdoor unit side, insulate the piping, including valves.
3) Apply piping tape (G) starting from the connection on the outdoor unit.
• When piping has to be installed through a ceiling, closet or where the temperature
and humidity are high, use additional field-supplied insulation to prevent condensa-
tion.

4. PURGING PROCEDURES, LEAK TEST, AND TEST RUN

4-1. PURGING PROCEDURES AND LEAK TEST
1) Remove service port caps from stop valves on both sides of refrigerant lines. (The stop
valves are fully closed when shipped.) Leave closed.
2) Connect gauge manifold to ports of stop valves.
3) Evacuate the system to 4000 microns from both service valves. System manifold gaug-
es must not be used to measure vacuum. A micron gauge must be used at all times.
Break the vacuum with Nitrogen(N2) into the discharge service valve to 0 PSIG.
4) Evacuate the system to 1500 microns. Break the vacuum with Nitrogen(N2) into the
discharge service valve to 0 PSIG.
5) Evacuate the system to 500 microns.
6) Close gauge manifold valves, stop the pump, and conduct a 30 minute rise test.
7) System should hold 500 microns for a minimum of 1 hour.
8) Fully open all stop valves on both sides of gas pipe and liquid pipe. Operating without
fully opening lowers the performance and this causes trouble.
9) Refer to 1-3 and charge the prescribed amount of additional refrigerant if needed. Be
sure to charge slowly with liquid refrigerant. Otherwise composition of the refrigerant in
the system may be changed and affect performance of the air conditioner.
10) Remove gauge manifolds and replace service port caps and tighten.
11) Leak test
Tightening torque
Clutch Wing nut
ft-lb
type tool type tool
(kgf•cm)
for R22 for R22
10 to 13
13.7 to 17.7
(140 to 180)
0.06 to 0.08
(1.5 to 2.0)
25 to 30
34.3 to 41.2
(350 to 420)
36 to 42
49.0 to 56.4
(500 to 575)
0.08 to 0.10
(2.0 to 2.5)
54 to 58
73.5 to 78.4
(750 to 800)
WARNING
N•m
Burr
Flaring tool
Clutch type
Smooth all around
Even length
all around
Stop valve cap
*4 to 5 turns
(Torque 15 to
22 ft-lb, 19.6 to
*Close
29.4 N•m, 200
*Open
to 300 kgf▪cm)
Hexagonal wrench
Service port cap
(Torque 10 to 13 ft
-Ib, 13.7 to 17.7 N•m,
140 to 180 kgf•cm)
Precautions when using the control valve When attaching the control valve
A
Control valve
Open
Close
Body
Good
Copper
pipe
Tilted
Fig. 1
Copper pipe
Spare reamer
Pipe cutter
Copper pipe
Die
Wing nut type
Flare nut
Fig. 4
Inside is shin-
ing without any
scratches.
Fig. 6
Compound pressure gauge
–14.7 psi [Gauge]
(for R410A)
(–0.101 Mpa)
Pressure gauge
(for R410A)
Stop valve for LIQUID
Handle
Low
Charge hose
Stop valve for
(for R410A)
GAS
Adapter for pre-
venting the back
flow Vacuum pump (or the vacuum
pump with the function to
prevent the back flow)
to the service port, valve core may
deform or loosen if excess pressure
is applied. This may cause gas leak.
When attaching the control valve to
the service port, make sure that the
Service port
valve core is in closed position, and
then tighten part A. Do not tighten
part A or turn the body when valve
Charge hose
core is in open position.
No good
Uneven Burred
Fig. 2
Fig. 3
Fig. 5
B
Gauge manifold valve
(for R410A)
Handle High