Mitsubishi Heavy Industries FDC112KXEN6 Technical Manual page 211

Work procedure
q Remove the flare nut and blind flanges on the pipe of the indoor unit.
* Make sure to loosen the flare nut with holding the nut on pipe side 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 at this time, but it is not abnormal.)
● Pay attention whether the flare nut pops out. (as the indoor unit is sometimes pressured.)
w Make a flare on liquid pipe and gas pipe, and connect the refrigeration pipes on 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:
a) Make sure to loosen the flare nut with holding the nut on pipe side 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.
b) 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 by spanner with the specified torque mentioned in the table below. Make sure to hold the
pipe on the indoor unit securely by a spanner when tightening the nut in order to avoid unexpected stress on the
copper pipe.
e 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 or water dropping.
r Refrigerant is charged in the outdoor unit.
As for the additional refrigerant charge for the indoor unit and piping, refer to the installation manual attached to the
outdoor unit.
Pipe diameter
6.35
9.52
12.7
15.88
19.05
(vi) Drain pipe
Caution
q Install the drain pipe according to the installation manual in order to drain properly.
Imperfection in draining may cause flood indoors and wetting the household goods, etc.
w Do not put the drain pipe directly into the ditch where toxic gas such as sulfur, the other harmful andinflammable gas is
generated. Toxic gas would flow into the room and it would cause serious damage to userís health and safety (some
poisoning or deficiency of oxygen). In addition, it may cause corrosion of heat exchanger and bad smell.
e Connect the pipe securely to avoid water leakage from the joint.
r Insulate the pipe properly to avoid condensation drop.
t Check if the water can flow out properly from both the drain outlet on the indoor unit and the end of the drain pipe after
installation.
y Make sure to make descending slope of greater than 1/100 and do not make up-down bend and/or trap in the midway. In
addition, do not put air vent on the drain pipe. Check if water is drained out properly from the pipe during commission-
ing. Also, keep sufficient space for inspection and maintenance.
Work procedure
q Insert the supplied drain hose (the end made of soft PVC) to the step of the drain socket on the indoor unit and fix it
securely with the clamp.
a) Do not apply adhesives on this end.
b) Do not use acetone-based adhesives to
connect to the drain socket.
rain socket
Tightening torque Nám
14 to 18
34 to 42
49 to 61
68 to 82
100 to 120
Stage difflernce part
Unit
rain hose
rain socket
Strap (Accessory)
The thickness of insulation should be 20mm or more.
VP-20
(Prepare on site)
Pipe cover (big)
(For insulation) (Accessory)
rain hose
(Accessory)
Clamp (Accessory)
Pipe cover (For insulation)
(No adhesive allowed)
Pipe cover (small)
(For insulation) (Accessory)
207
- -
Pipe cover (Accessory)
VP-25
(Prepare on site)
Joint for VP-20
(Prepare on site)
(Prepare on site)