Mitsubishi Electric FDF100VSXVD Technical Manual page 59

Refrigerant piping
Caution
Use the new refrigerant pipe.
When re-using the existing pipe system for R22 or R407C, pay attention to the following
items.
Change the flare nuts with the attached ones (JIS category 2), and reprocess the flare
parts.
Do not use thin-walled pipes.
Use phosphorus deoxidized copper alloy seamless pipe (C1220T specified in JIS
H3300) for refrigeration pipe installation.
In addition, make sure there is no damage both inside and outside of the pipe, and no
harmful substances such as sulfur, oxide, dust or a contaminant stuck on the pipes.
Do not use any refrigerant other than R410A.
Using other refrigerant except R410A (R22 etc.) may degrade inside refrigeration oil.
And if air getting into refrigerant circuit, it may cause anomaously high pres and may
result in burst, etc.
Store the copper pipes indoors and seal the both end of them until they are brazed in
order to avoid any dust, dirt or water getting into pipe. Otherwise it will cause degrada-
tion of refrigeration oil and compressor breakdown, etc.
Use special tools for R410 refrigerant.
Work procedure
1. Remove the flare nuts and flare caps from the pipes of the indoor unit.
Make sure to loosen the flare nut by holding the flared male fitting with a spanner
and giving torque to the nut with another spanner in order to avoid unexpected
stress to the copper pipe, and then remove them.
(Gas may come out a little at this time, but it is no anomaly.)
Pay attention that the flare nut may pop out.
(Because it is sometimes pressurized in the indoor unit)
2. Make a flare on liquid pipe and gas pipe, and connect the refrigrant pipes to the indoor
unit.
Bend the pipe with as big radius as possible and do not bend the pipe repeatedly. In
addition, do not twist and crush the pipes.
Do a flare connection as follows:
Make sure to loosen the flare nut by holding the flared male fitting with a spanner
and giving torque to the nut with another spanner in order to avoid unexpected
stress to the copper pipe, and then remove them.
When fastening the flare nut, align the refrigeration pipe with the center of flare nut,
screw the nut for 3-4 times by hand and then tighten it with a spanner within the
specified torque mentioned in the table below.
Make sure to hold the flared male fitting on the indoor unit side with another spanner
when tightening the nut in order to avoid unexpected stress on the copper pipe.
3. Cover the flare connection part of the indoor unit with attached insulation material after
a gas leakage inspection, and tighten both ends with attached straps.
Make sure to insulate both gas pipes and liquid pipes completely.
Incomplete insulation may cause dew condensation and dew dropping.
4. Refrigerant is pre-charged in the outdoor unit.
As for the additional refrigerant charge for the indoor unit and piping, refer to the instal-
lation manual attached to the outdoor unit.
Pipe cover (Accessory)
Strap (Accessory)
The thickness of insulation should be 20mm or more.
Pipe diameter Tightening torque N·m
6.35
9.52
12.7
15.88
19.05
14 to 18
34 to 42
49 to 61
68 to 82
100 to 120
Refrigerant piping (Continued)
◆ Pipe and wire extracting position
600
ATTENTION:
• Do not cut off the flange at the hole on the
base plate for the downward extraction.
Downward extraction
Liquid pipe
Pipe cover
(For liquid pipe)
(Unit front)
For downward
extraction
(ø100 hole)
440
(Unit bottom)
Liquid pipe
Pipe cover
(Liquid pipe)
For backward extraction
(ø100 knock-out hole)
(Unit front)
Liquid pipe
Pipe cover
(For liquid pipe)
(Unit front)
For side extraction (at right and left)
(ø100 knock-out hole)
- - 58 58 - -
'11 • PAC-T-160
Gas pipe
Liquid pipe
48
93
Gas pipe
Pipe cover
(For gas pipe)
(Unit right side)
61
Backward extraction
Gas pipe
Pipe cover
(Gas pipe)
(Unit right side)
85
Sideward extraction
Gas pipe
Pipe cover
(For gas pipe)
143
(Unit right side)