Where An Existing Pipe System Is Utilized, Different One-Way Pipe Length Restrictions Should Apply Depending On Its Pipe Size; For More Information, Please See "5. Utilization Of Existing Piping; If Touching With An Internal Component, It Will Generate Abnormal Sounds And/Or Vibrations; Fix Both Liquid And Gas Service Valves At The Valve Main Bodies As Illustrated On The Right - Mitsubishi Heavy Industries FDE40ZMXVG Technical Manual

Since drain water generated by defrost control may freeze, following measures are required.
• Do not execute drain piping work by using a drain elbow and drain grommets (accessories).
[Refer to Drain piping work.]
2. REFRIGERANT PIPING WORK
1) Restrictions on unit installation and use
• Check the following points in light of the indoor unit specifications and the installation site.
• Observe the following restrictions on unit installation and use. Improper installation can result in a compressor failure or performance degradation.
Restrictions
Main pipe length
When the outdoor unit is positioned higher,
Elevation difference between
indoor and outdoor units
When the outdoor unit is positioned lower,
• The use restrictions appearing in the table above are applicable to the standard pipe size combinations shown in the table below.
CAUTION

Where an existing pipe system is utilized, different one-way pipe length restrictions should apply depending on its pipe size.

For more information, please see "5. UTILIZATION OF EXISTING PIPING."

2) Determination of pipe size
Determine refrigerant pipe size pursuant to the following guidelines
based on the indoor unit specifications.
Model 40, 50, 60
Gas pipe
ø12.7
Outdoor unit connected
Flare
Refrigerant piping (branch pipe L) ø12.7
Indoor unit connected ø12.7
3) Refrigerant pipe wall thickness and material
• Select refrigerant pipes of the table shown on the right wall thickness and material as specified
for each pipe size.
NOTE Select pipes having a wall thickness larger than the specified minimum pipe thickness.
4) On-site piping work
Take care so that installed pipes may not touch components within a unit.
IMPORTANT

If touching with an internal component, it will generate abnormal sounds and/or vibrations.

Please remove the screw of a side cover and
How to remove the side cover
remove to the front.
• Carry out the on site piping work with the service valve fully closed.
• Give sufficient protection to a pipe end (compressed and blazed, or with an
adhesive tape) so that water or foreign matters may not enter the piping.
• Bend a pipe to a radius as large as practical (R100 ~ R150). Do not bend a pipe
repeatedly to correct its form.
• Flare connection is used between the unit and refrigerant pipe. Flare a pipe after
engaging a flare nut onto it. Flare dimensions for R410A are different from
those for conventional R407C. Although we recommend the use of flaring tools
designed specifically for R410A, conventional flaring tools can also be used by
adjusting the measurement of protrusion B with a protrusion control gauge.
• The pipe should be anchored every 1.5m or less to isolate the vibration.
• Tighten a flare joint securely with a double spanner.
Do not apply force beyond proper fastening torque in tightening the flare nut.
CAUTION
Fix both liquid and gas service valves at the valve main bodies as illustrated on the right, and then fasten them,
applying appropriate fastening torque.
Service valve size (mm) Tightening torque (N·m)
ø6.35 (1/4")
ø12.7 (1/2")
Marks appearing in the
Dimensional restrictions
drawing on the right
30m or less
20m or less
20m or less
When pipe is brazing.
About brazing
Brazing must be performed under a nitrogen gas flow.
Liquid pipe
Without nitrogen gas, a large quantity of foreign matters
ø6.35
(oxidized film) are created, causing a critical failure from
Flare
capillary tube or expansion valve clogging.
ø6.35
ø6.35
Minimum pipe wall thickness [mm]
*Phosphorus deoxidized seamless copper pipe ICS 23.040.15, ICS 77.150.30
Tightening angle ( ) Recommended length of a tool handle (mm)
~ ~
14 18 45 60
~ ~
49 61 30 45
• Refer to the above illustrations for information regarding concrete foundations.
• Install the unit in a level area. (With a gradient of 5mm or less.) Improper installation can result in a
compressor failure, broken piping within the unit and abnormal noise generation.
L
H
H
H
Outdoor unit
Plug the end of the pipe with tape, or other
material, and fill the pipe with nitrogen gas.
Taping
Only use nitrogen gas (N
Pipe diameter [mm] ø6.35 ø12.7
0.8 0.8
Pipe material* O-type pipe O-type pipe
A
Side cover
The screw of the
side cover is
tightened securely.
150
Do not hold the valve cap area with a spanner.
250
Indoor unit
L
Primary side Secondary side
Station valve
0.5MPa
Hand
<N2>
Nitrogen
Relief valve
gas
)
Brazing
2
Flared pipe end : A
(mm)
Copper pipe 0
A
outer diameter –04
ø6.35 9.1
ø12.7 16.6
Copper pipe protrusion for flaring : B
(mm)
Copper pipe In the case of a rigid (clutch) type
outer diameter
With an R410A tool With a conventional tool
ø6.35
~ ~
0 0.5 1.0 1.5
ø12.7
Use a torque wrench. If a torque wrench is
not available, fasten the flare nut manually
first and then tighten it further, using the
left table as a guide.
4. ELECTRICAL W
Electrical installation work must
Electrical installation work must
• Do not use any supply cord lig
• braided cord (code designati
• ordinary tough rubber sheath
• flat twin tinsel cord (code de
Use polychloroprene sheathed
cords of parts of appliances fo
• Ground the unit. Do not conne
or telephone grounding wire.
If improperly grounded, an ele
• A grounding wire must be con
grounding wire longer than the
• The installation of an impulse w
failure to install an earth leakag
or a fire.
• Do not turn on the power until
• Do not use a condensive capac
(It dose not improve power fac
• For power source cables, use c