Mitsubishi Heavy Industries FDTCVA SERIES Technical Manual page 219

(iv) Double twin type
Models FDCVA802, 1002 [Branch pipe set : DIS-WA1 × 2set, DIS-WB1 × 1set]
Item
Indoor unit
combinations
Model
20 + 20 + 20 + 20
FDCVA802
25 + 25 + 25 + 25
FDCVA1002
Notes (1) Use the irregular fittings
(branch ~ indoor unit) liquid piping size φ 9.52.
(2) Mark is to FDCVA802 only.
Chart of shapes of branch piping parts (DIS-WB1)
Gas pipe Mark Liquid pipe
ID15.88
ID9.52
ID25.4
19
10
39
ID15.88
Notes (1) to in the drawing include parts provided in the branch piping set. It shows the codes for the shapes of different-diameter connections.
(2) Branch piping should always be arranged to have level or perpendicular branch. (Refer to the 216 page for details.)
(3) Mark shows for the FDCVA802 model only.
Notes (1) For model FDCVA802, always use φ12.7 mm liquid pipes, when the length of the main "L" exceeds 40 m. If φ9.52 mm pipes are used in an installation
having over 40 m piping, they can cause performance degradation and/or water leaks from an indoor unit.
When the pipes length measures 60 m or longer for the model FDCVA802, we recommend the use of a φ12.7 mm liquid main.
(2) One-way pipe length should measure 5 m at a minimum. If the pipe length measures less than 5 m, then reduce the quantity of charged refrigerant. If you
need to recover or recharge refrigerant, contact our sales agent found in your neighborhood.
(b) How to use pipe reducer (Attached to FDCVA802, 1002 only)
• φ 22.22 (OD) size of the refrigerant gas pipe can be used by using the accessory pipe B, although φ 25.4 (OD) size of the
refrigerant gas pipe is standard.
(When φ 25.4 (OD) size of the refrigerant gas pipe is used, the accessory pipe B is unnecssary.)
( * ) OD: Outer diameter.
This accessory pipe includes the following parts.
φ19.05
(Flare connection)
( * ) ID: Inner diameter.
Install this accessory pipe according to the following.
Accessory pipe A
DIS-WA1
DIS-WB1
Gas line
Outdoor unit
Liquid line
DIS-WA1
Liquid pipe
Main pipe 1st branch pipe
φ 9.52 × t 0.8
φ 9.52 × t 0.8
φ 12.7 × t 0.8
supplied with the branch piping set on the indoor unit side, and make the branch piping
Mark Reducer
ID9.52
OD12.7 ID9.51
10
80
ID9.52
190
A
ID22.22
Brazing
Field piping φ22.22(OD)
2nd branch pipe Main pipe 1st branch pipe
φ 9.52 × t 0.8 φ 25.4 × t 1.0 φ 15.88 × t 1.0
Chart of shapes of branch piping parts (DIS-WA1)
Mark Gas pipe Mark
ID15.88
ID9.52
ID15.88
11
8
24
ID15.88
Accessory pipe B
Branch piping parts (DIS-WB1,DIS-TB1)
In case of V-multi
218
- -
Indoor unit
Gas pipe
2nd branch pipe
φ 12.7 × t 0.8
φ 15.88 × t 1.0
Liquid pipe Mark Reducer
φ6.35
ID9.52
flared nut
50
8
ID9.52
105
2 piece
ID9.52
OD15.88 ID12.7
210
10
80
2 piece
B
ID22.22
OD25.4
Mark