Mitsubishi Heavy Industries FDTC40ZIXVD Data Book page 210

Since drain water generated by defrost control may freeze, following measures are required.
Don't execute drain piping work by using a drain elbow and drain grommets (optional parts). [Refer to Drain
piping work.]
Recommend setting Defrost Control (SW3-1) and Snow Guard Fan Control (SW3-2). [Refer to Setting SW3-1,
SW3-2.]
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.
Gas pipe
Outdoor unit connected
Flare
Refrigerant piping (branch pipeL)
Indoor unit connected
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.
How to remove the side cover
Please remove the screw of a side cover and remove to the front.
Carry out the on site piping work with the operation 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.
CAUTION Do not apply force beyond proper fastening torque in tightening the flare nut.
Fix both liquid and gas operation valves at the valve main bodies as illustrated on the right, and then fasten them,
applying appropriate fastening torque.
Operation valve size (mm) Tightening torque (N m)
6.35 (1/4") 14 18
12.7 (1/2")
49 61
5) Air tightness test
Although outdoor and indoor units themselves have been tested for air tightness at the factory, check the connecting pipes after the installation work for air tightness from the
operation valve's check joint equipped on the outdoor unit side. While conducting a test, keep the operation valve shut all the time.
a) Raise the pressure to 0.5 MPa, and then stop. Leave it for five minutes to see if the pressure drops.
b) Then raise the pressure to 1.5 MPa, and stop. Leave it for five more minutes to see if the pressure drops.
c) Then raise the pressure to the specified level (4.15 MPa), and record the ambient temperature and the pressure.
Dimensional restrictions Marks appearing in the drawing on the right
30m or less
20m or less
20m or less
When pipe is brazing.
About brazing
Model 40, 50, 60
Brazing must be performed under a nitrogen gas flow.
Liquid pipe
Without nitrogen gas, a large quantity of foreign matters (oxidized film) are created,
12.7 6.35
causing a critical failure from capillary tube or expansion valve clogging.
Flare
12.7 6.35
12.7 6.35
Tightening angle ( ) Recommended length of a tool handle (mm)
45 60 150
30 45 250
The protrusion of an anchor bolt on the front side must be kept within 15 mm.
Securely install the unit so that it does not fall over during earthquakes or strong winds, etc.
Refer to the above illustrations for information regarding concrete foundations.
Install the unit in a level area. (With a gradient of 5 mm 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
Primary side Secondary side
Plug the end of the pipe with tape, or other
Station valve
material, and fill the pipe with nitrogen gas.
0.5MPa
Hand
N
Taping
2
Nitrogen
Relief valve
gas
Only use nitrogen gas (N )
2 Brazing
Pipe diameter [mm] 6.35
Minimum pipe wall thickness [mm] 0.8
Pipe material* O-type pipe
*Phosphorus deoxidized seamless copper pipe ICS 23.040.15, ICS 77.150.30
A
Flared pipe end : A
Copper pipe protrusion for flaring : B
Screw
Side cover
Do not hold the valve cap area with a spanner.
Indoor unit
L
12.7
0.8
O-type pipe
(mm)
Copper
0
pipe outer
0 4
diameter
6.35 9 1
12.7 16.6
(mm)
Copper
In the case of a rigid (clutch) type
pipe outer
diameter With an R410A tool With a conventional tool
6.35
0 0.5 1.0 1.5
12.7
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.
Gas side
operation valve
Outdoor unit Indoor unit
Check joint
4. ELECTRICAL WI
Electrical installation work must be perfo
Electrical installation work must be exec
Do not use any supply cord lighter th
braided cord (code designation 60
ordinary tough rubber sheathed co
flat twin tinsel cord (code designat
Use polychloroprene sheathed flexib
Ground the unit. Do not connect the grou
If impropery grounded, an electric s
A grounding wire must be connected
The installation of an impulse withst
acccident such as an electric shock
Do not turn on the power until the el
Do not use a condensive capacitor fo
an abnormal overheat accident)
For power supply cables, use condui
Do not lay electronic control cables (r
in the malfunctioning or a failure of
Fasten cables so that may not touch
When cables are connected, make su
terminal connection and then attach
penetrates into the box.)
Always use a three-core cable for an