Indoor/Outdoor Units Connection Finishing And - Mitsubishi Electric MXZ-4A80VA Installation Manual

5. INDOOR/OUTDOOR UNITS CONNECTION FINISHING AND TEST RUN
5-1 FLARED CONNECTIONS
PIPE LENGTH AND HEIGHT DIFFERENCE
Limits 4A80VA
Pipe length per indoor unit 25 m max.
Total pipe length for multi-system 70 m max.
Height difference 10 m max.
No. of bends per indoor unit 25 max.
Total No. of bends for multi-system 70 max.
Refrigerant adjustment ....... If pipe length exceeds 40 m, additional refrigerant (R410A) charge is required.
(The outdoor unit is charged with refrigerant for total pipe length up to 40 m.)
Up to 40 m
Pipe length
Exceeding 40 m
20 g/m × (refrigerant piping length(m)-40)
Refrigerant to be added
Indoor unit Î UNIT
Ç UNIT
Indoor unit
ı UNIT
Indoor unit
Å UNIT
Indoor unit
• For pipe size, see the table below.
SELECTING PIPE SIZE
The diameter of connection pipes differs according to the type and capacity of indoor units. Match the diameters
of connection pipes for indoor and outdoor units according to the following table.
Model Allowable
Pipe size for indoor unit
name connection pipe size
22 Liquid pipe ø6.35 mm ø6.35 mm
25 Gas pipe ø9.52 mm ø9.52 mm
Liquid pipe ø6.35 mm ø6.35 mm
35
Gas pipe ø9.52 mm ø9.52 mm
Liquid pipe ø6.35 mm ø6.35 mm
50
Gas pipe ø12.7 mm ø12.7 mm
Liquid pipe ø6.35 mm ø6.35 mm
60
Gas pipe ø15.88 mm ø15.88 mm
Liquid pipe ø9.52 mm ø9.52 mm
71
Gas pipe ø15.88 mm ø15.88 mm
No additional charge is required.
Additional charge is required.
(Refer to the table below.)
Outdoor
unit
(MXZ-4A80VA)
Valve size for outdoor unit
Liquid pipe
Å UNIT
Gas pipe
Liquid pipe
ı UNIT
Gas pipe
Liquid pipe
Ç UNIT
Gas pipe
Liquid pipe
Î UNIT
Gas pipe
* Connections at outdoor unit are described as unit A, B, C and D below corresponding to the indica-
tion on each valve.
• If the diameter of connection pipes does not match the diameter of pipe end connections, use optional
different-diameter joints.
• When connecting the model 50 to either unit B, C or D, use optional different-diameter joints MAC-A454JP
because the valve size of gas pipes for the outdoor unit is ø9.52 mm.
• When connecting the model 22, 25 or 35 to unit A, use optional different-diameter joints MAC-A455JP be-
cause the valve size of gas pipes for the outdoor unit is ø12.7 mm.
• When connecting the model 60 to unit A, use optional different-diameter joints MAC-A456JP because the
valve size of gas pipes for the outdoor unit is ø12.7 mm.
• When connecting the model 60 to either unit B, C or D, use optional different-diameter joints PAC-SG76RJ
because the valve size of gas pipes for the outdoor unit is ø9.52 mm.
• When connecting the model 71 to unit A, use optional different-diameter joints MAC-A456JP and PAC-493PI
because the valve size of gas pipe and liquid pipe for the outdoor unit is ø12.7 mm and ø6.35 mm.
• When connecting the model 71 to either unit B, C or D, use optional different-diameter joints PAC-SG76RJ and
PAC-493PI because the valve size of gas pipe and liquid pipe for the outdoor unit is ø9.52 mm and ø6.35 mm.
PIPING PREPARATION
1 If you use commercially available copper pipes, use the following table for pipe specifications.
Outside diameter
Liquid pipe
Gas pipe
Gas pipe
Gas pipe ø15.88 mm
2 For insulation material, use 8 mm-thick heat-insulating expended polyethylene with a specific gravity of 0.045.
3 Ensure that the 2 refrigerant pipes are insulated to prevent condensation.
4 Refrigerant pipe bending radius must be 100 mm or more.
CAUTION:
Be sure to use the insulation of specified thickness. Excessive thickness may cause incorrect installa-
tion of the indoor unit and lack of thickness may cause dew drippage.
5-2 FLARING WORK
ø6.35 mm • Main cause of gas leakage is defect in flaring work.
ø12.7 mm
Perform flaring work correctly in the following procedure.
ø6.35 mm
ø9.52 mm
1. Pipe cutting
ø6.35 mm
• Cut the copper pipe correctly with pipe cutter.
ø9.52 mm
ø6.35 mm
2. Burrs removal
ø9.52 mm
• Completely remove all burrs from the cut cross
section of the pipe.
• Put the end of the copper pipe downward to pre-
vent burrs from dropping in the pipe.
3. Putting nut on
• Remove flare nuts attached to indoor and outdoor
units, then put them on pipe having completed
burr removal.
(not possible to put them on after flaring work)
• Flare nut for R410A pipe may differ from R22 pipe
depending on the diameter of pipe.
6
Wall thickness
ø6.35 mm 0.8 mm
ø9.52 mm 0.8 mm
ø12.7 mm 1.0 mm
1.0 mm
Copper
pipe
No good
Good
Tilted Uneven Burred
90°
Copper pipe
Burr
Spare
reamer
Pipe cutter
Flare nut
Copper pipe