Mitsubishi Electric MXZ-8B48NA Installation Manual page 8

5. Installing the refrigerant piping
Fig. 5-4
45 2
Flare cutting dimensions
Flare nut tightening torque
Fig. 5-5
A (Fig. 5-5)
Copper pipe O.D.
(mm) (inch)
ø6.35 (1/4)
ø9.52 (3/8)
ø12.7 (1/2)
ø15.88 (5/8)
Copper pipe O.D. Flare nut O.D.
(mm) (inch) (mm) (inch)
ø6.35 (1/4) 17 (11/16)
ø6.35 (1/4) 22 (7/8)
ø9.52 (3/8) 22 (7/8)
ø9.52 (3/8) 26 (1-1/4)
ø12.7 (1/2) 26 (1-1/4)
ø12.7 (1/2) 29 (1-1/8)
ø15.88 (5/8) 29 (1-1/8)
ø15.88 (5/8) 36 (1-7/16)
Fig. 5-6
8
A
Liquid pipe
B
Gas pipe
C
Insulation
D
Taping
Flare dimensions
øA dimensions (mm) (inch)
8.7 - 9.1 (5/16 - 3/8)
12.8 - 13.2 (1/2)
16.2 - 16.6 (5/8)
19.3 - 19.7 (3/4)
Tightening torque
(N·m)* (ft·lb)
14 - 18 (10 - 13)
34 - 42 (25 - 30)
34 - 42 (25 - 30)
49 - 61 (35-44)
49 - 61 (35-44)
68 - 82 (49 - 59)
68 - 82 (49 - 59)
100 - 120 (71 - 87)
* 1 N·m 10 kgf·cm
A
Die
Copper pipe
Refrigerant collection when relocating the indoor and outdoor
units (pump down)
1 Connect a gauge manifold valve (pressure gauge included) to the service port
near the gas stop valve of the outdoor unit so that the refrigerant pressure can
be measured.
2 Turn on the power supply (circuit breaker).
3 Close the liquid stop valve, and then perform the test run for cooling operation
(SW4-1: ON and SW4-2: OFF).
* Be sure to wait at least 3 minutes after turning on the power supply before
setting SW4-1 and SW4-2. If the DIP switches are set before 3 minutes has
elapsed, the test run may not start.
4 Fully close the gas stop valve when the pressure reading on the gauge drops
to 0.05 - 0.00 MPa* (7.3-0 PSIG) (approximately 0.5 - 0.0 kgf/cm
* If too much refrigerant has been added to the air conditioner system, the
pressure may not drop to 0.5 kgf/cm
ing device to collect all of the refrigerant in the system, and then recharge
the system with the correct amount of refrigerant after the indoor and outdoor
units have been relocated.
5 Stop the air conditioner operation (SW4-1: OFF and SW4-2: OFF).
6 Turn off the power supply (circuit breaker).
Warning:
When pumping down the refrigerant, stop the compressor before disconnect-
ing the refrigerant pipes. The compressor may burst if air etc. get into it.
5.5. Connecting pipes (Fig. 5-4) (Fig. 5-5)
When commercially available copper pipes are used, insulate both the liquid and
gas pipes separately with commercially available insulation materials (heat-resis-
tant to 100 °C, 212 °F or more, thickness of 12 mm, 1/2 inch or more). (Fig. 5-4)
• The indoor parts of the drain pipe should be wrapped with polyethylene foam in-
sulation materials (specifi c gravity of 0.03, thickness of 9 mm (3/8 inch) or more).
[Fig. 5-5]
• Apply thin layer of refrigerant oil to pipe and joint seating surface before tighten-
ing fl are nut. A
• Use two wrenches to tighten piping connections. B
• Use leak detector or soapy water to check for gas leaks after connections are
completed.
• Apply refrigerating machine oil over the entire fl are seat surface. C
• Use the fl are nuts as follows. D
Warning:
When installing the unit, securely connect the refrigerant pipes before start-
ing the compressor.
■
Pipe size (Outdoor unit-Branch box)
Pipe size Liquid ø9.52 (3/8)
The lineup of a connectable indoor unit
(ømm) (inch)
Gas ø15.88 (5/8)
depends on a district/areas/country.
■
Pipe size (Branch box-Indoor unit) *Case of M series or S series Indoor unit
Indoor
(BTU/h) 06 09
unit type
ø6.35 ø6.35
Pipe size Liquid
(1/4) (1/4)
(ømm)
ø9.52 ø9.52
(inch)
Gas
(3/8) (3/8)
■
Pipe size (Branch box-Indoor unit) *Case of P series indoor unit
Indoor unit type (BTU/h) 18
Pipe size Liquid ø6.35 (1/4)
(ømm) (inch)
Gas ø12.7 (1/2)
• When bending the pipes, be careful not to break them. Bend radii of 100 mm (4
inch) to 150 mm (6 inch) are suffi cient.
• Make sure the pipes do not contact the compressor. Abnormal noise or vibration
may result.
1 Pipes must be connected starting from the indoor unit.
Flare nuts must be tightened with a torque wrench.
2 Flare the liquid pipes and gas pipes and apply a thin layer of refrigeration oil (Ap-
plied on site).
• When usual pipe sealing is used, refer to Table 2 for fl aring of R410A refrigerant
pipes.
The size adjustment gauge can be used to confi rm A measurements.
Table 2 (Fig. 5-6)
Copper pipe O.D. Flare tool for R410A
ø6.35 (1/4) 0 - 0.5 (0 - 1/64)
ø9.52 (3/8) 0 - 0.5 (0 - 1/64)
ø12.7 (1/2) 0 - 0.5 (0 - 1/64)
ø15.88 (5/8) 0 - 0.5 (0 - 1/64)
).
2
2 . If this occurs, use a refrigerant collect-
12 15 18 24
ø6.35 ø6.35 ø6.35 ø9.52
(1/4) (1/4) (1/4) (3/8)
ø9.52 ø12.7 ø12.7 ø15.88
(3/8) (1/2) (1/2) (5/8)
24 30
ø9.52 (3/8) ø9.52 (3/8)
ø15.88 (5/8) ø15.88 (5/8)
mm (inch)
A
Flare tool for R22·R407C
Clutch type
1.0 - 1.5 (3/64 - 1/16)
1.0 - 1.5 (3/64 - 1/16)
1.0 - 1.5 (3/64 - 1/16)
1.0 - 1.5 (3/64 - 1/16)