Blowout Changing Procedure; Refrigerant Pipe And Drain Pipe Specifications; Refrigerant Pipe And Drain Pipe Size; Connecting Refrigerant Pipes And Drain Pipes - Mitsubishi Electric PFFY-P-NEMU-E Installation Manual

4.3. Blowout changing procedure

(For PFFY-P-NRMU Series only)
To change the blowout from upward to forward in the case of the flush type units
PFFY-P-NRMU Series, follow the procedure below.
F Remove the screws, lift to remove the blowout hole in direction A, turn the
blowout hole 180° B, and set the hole forward C.
[Fig. 4.3.1] (P.3)
G Set the blowout hole just as it was removed, and tighten the screws.
[Fig. 4.3.2] (P.3)
Notes:
• When handling the blowout hole, be careful that the insulating material
lined inside is not peeled off.
• Be careful not to get your hand injured by sheet metal edges.

5. Refrigerant pipe and drain pipe specifications

To avoid dew drops, provide sufficient antisweating and insulating work to the
refrigerant and drain pipes.
When using commercially available refrigerant pipes, be sure to wind commer-
cially available insulating material (with a heat-resisting temperature of more than
100 °C [212 °F] and thickness given below) onto both liquid and gas pipes.
Be also sure to wind commercially available insulating material (with a form poly-
ethylene's specific gravity of 0.03 and thickness given below) onto all pipes which
pass through rooms.

5.1. Refrigerant pipe and drain pipe size

[Fig. 5.1.1] (P.3)
Flare cutting dimensions
Refrigerant pipe sizes & Flare nut tightening torque
Apply refrigerating machine oil over the entire flare seat surface
Flare cutting dimensions
Copper pipe O.D. (mm) [in]
φ 15.88 [5/8]
Refrigerant pipe sizes & Flare nut tightening torque
Liquid pipe
Tightening
Pipe size
(mm) [in]
O.D. φ 6.35 [1/4]
P06/08/12/15 14 – 18
O.D. φ 6.35 [1/4]
P18 34 – 42
O.D. φ 9.52 [3/8]
P24 34 – 42
* Use the provided flare nut for the following pipes: Liquid pipe and gas pipe of P18.
[Fig. 5.1.2] (P.3)
Refrigerant pipe flare connection (for gas)
Refrigerant pipe flare connection (for liquid)
Drain pan
Hose (accessory) (External diameter φ 27 mm [1-1/16in] (end φ 20 mm [13/16 in]))
Air filter

6. Connecting refrigerant pipes and drain pipes

6.1. Refrigerant piping work

This piping work must be done in accordance with the installation manual for the
outdoor unit.
• For constraints on pipe length and allowable difference of elevation, refer to
the outdoor unit manual.
• The method of pipe connection is flare connection.
Cautions on refrigerant piping
Be sure to use non-oxidative brazing for brazing to ensure that no for-
eign matter or moisture enter into the pipe.
Be sure to apply refrigerating machine oil over the flare connection
seating surface and tighten the connection using a double spanner.
Warning:
When installing and moving the unit, do not charge it with refrigerant other
than the refrigerant specified on the unit.
- Mixing of a different refrigerant, air, etc. may cause the refrigerant cycle to
malfunction and result in severe damage.
8
φ 6.35 [1/4]
φ 9.52 [3/8]
φ 12.7 [1/2]
R410A
Gas pipe
Tightening
Pipe size
torque torque
(mm) [in]
(N·m) (N·m)
O.D. φ 12.7 [1/2]
49 – 61
O.D. φ 12.7 [1/2]
68 – 82
O.D. φ 15.88 [5/8]
68 – 82
Stainer
Control box
• When connecting a duct to the blowout hole, be sure to insert the duct
to the hilt of the blowout hole, and provide insulating material over the
duct. Also, seal the joints between the duct and unit body with alumi-
num tape. (H)
• If you want to use the unit without connecting a duct to the blowout
hole, be sure to provide soft urethane form around the blowout hole in
order to prevent the blowout hole section from dew condensation. (I)
[Fig. 4.3.3] (P.3)
Duct
Tape
Blowout hole section
Insulating material
Insulating material (10 mm [13/32 in] in thickness. Be provided around the
blowout hole section.)
A Select the thickness of insulating material by pipe size.
Pipe size
6.4 mm to 25.4 mm
[1/4 in to 1 in]
28.6 mm to 38.1 mm
[1-1/8 in to 1-1/2 in]
B If the unit is used on the highest story of a building and under conditions of
high temperature and humidity, it is necessary to use pipe size and insulating
material's thickness more than those given in the table above.
C If there are customer's specifications, simply follow them.
Flare dimensions φ A dimensions (mm) [in]
12.8-13.2 [17/32~17/32]
16.2-16.6 [21/32~21/32]
19.3-19.7 [25/32~25/32]
R22
Liquid pipe
Tightening
Pipe size Pipe size
torque
(mm) [in] (mm) [in]
(N·m)
O.D. φ 6.35 [1/4] O.D. φ 12.7 [1/2]
14 – 18
O.D. φ 9.52 [3/8] O.D. φ 15.88 [5/8]
34 – 42*
O.D. φ 9.52 [3/8] O.D. φ 15.88 [5/8]
34 – 42
Caution:
• Use refrigerant piping made of C1220 (Cu-DHP) phosphorus deoxidized
copper as specified in the JIS H3300 "Copper and copper alloy seamless
pipes and tubes". In addition, be sure that the inner and outer surfaces
of the pipes are clean and free of hazardous sulphur, oxides, dust/dirt,
shaving particles, oils, moisture, or any other contaminant.
• Never use existing refrigerant piping.
- The large amount of chlorine in conventional refrigerant and refrigerator oil
in the existing piping will cause the new refrigerant to deteriorate.
• Store the piping to be used during installation indoors and keep both
ends of the piping sealed until just before brazing.
- If dust, dirt, or water gets into the refrigerant cycle, the oil will deteriorate
and the compressor may fail.
• Use Suniso 4GS or 3GS (small amount) refrigerator oil to coat the flare
and flange connection part. (For models using R22)
• Use ester oil, ether oil or alkylbenzene (small amount) as the refrigerator
oil to coat flares and flange connections. (For models using R410A)
- The refrigerant used in the unit is highly hygroscopic and mixes with water
and will degrade the refrigerator oil.
Insulating material's thickness
More than 10 mm
[13/32 in]
More than 15 mm
[19/32 in]
8.7-9.1 [11/32~6/16]
Flare nut O.D.
Gas pipe
Tightening Liquid
torque pipe
(N·m) (mm) [in]
49 – 61 17 [11/16]
68 – 82* 22 [7/8]
68 – 82 22 [7/8]
Gas
pipe
(mm) [in]
27 [1-3/32]
29 [1-5/32]
29 [1-5/32]