R(Y)(P)71~125B7
Split System air conditioners
4PW10931-1B
Installation manual
4
The minimal piping length should be 7.5
m. If installation is
performed with less field piping, the system will be overcharged
(abnormal HP, etc.). If the distance between indoor and outdoor unit
is less than 7.5 m, please make sure that the piping length is
≥
7.5 m
by additional bending of the pipes.
P
RECAUTIONS
ON
REFRIGERANT
PIPING
When a heat pump outdoor unit is installed below the indoor unit, the
following can occur:
■
when the unit stops, oil will return to the discharge side of the
compressor. When starting the unit, this can cause liquid (oil)
hammer.
■
the oil circulation will decrease
To solve these phenomena, provide oil traps in the gas pipe every
15 m if the level difference (H) is more than 15 m.
(See figure 5)
For R407C units:
Operating stop valve: see
figure 6
To open:
1
Remove the cap (1) and turn the shaft (2) counterclockwise with
hexagon socket screw keys.
2
Turn it all the way until the shaft stops.
3
Tighten the cap firmly.
To close:
1
Remove the cap and turn the shaft clockwise.
2
Tighten the shaft firmly until it reaches the sealed area (4) of the
body.
3
Tighten the cap firmly.
Precautions for connecting pipes
When the outdoor unit is installed above the indoor unit the following
can occur:
1
The condensated water on the stop valve can move to the
indoor unit. To avoid this, please cover the stop valve with
sealing material.
2
If the temperature is higher than 30°C and the humidity is higher
than RH 80%, then the thickness of the sealing materials should
be at least 20 mm in order to avoid condensation on the surface
of the sealing.
■
Please refer to the table for the dimensions for processing flares
and for the tightening torques. (Too much tightening will end up
in splitting of the flare.)
■
When connecting the flare nut, coat the flare both inside and
outside with refrigerant oil (R22), ether or ester oil (R407C) and
initially tighten by hand before tightening firmly.
■
Make sure to flow nitrogen gas through the pipe when brazing.
■
Take measures against contamination when installing pipes.
Prevent foreign materials like moisture and other impurities from
mixing into the system.
Great caution is needed when passing copper tubes through walls.
A
outdoor unit
B
indoor unit
C
gas pipe
D
liquid pipe
E
oil trap
NOTE
If the outdoor unit is installed above the indoor unit, oil
traps are not necessary.
Use R407C only when adding refrigerant
Installation tools:
Make sure to use installation tools (gauge manifold charge
hose, etc.) that are exclusively used for R407C
installations to withstand the pressure and to prevent
foreign materials (e.g. mineral oils and moisture) from
mixing into the system. Vacuum pump (use a 2-stage
vacuum pump with a non-return valve):
Make sure the pump oil does not flow oppositely into the
system while the pump is not working.
Use a vacuum pump which can evacuate to -100.7 kPa
(5 Torr, -755 mmHg).
NOTE
■
Refer to the table for stop valve tightening
torques.
■
Be sure to use both a spanner and a torque
wrench when connecting or disconnecting pipes
to or from the unit.
■
Use a charging hose with push rod when using
the service port (5).
■
Check for refrigerant gas leakage after tightening
the cap.
■
Make sure to keep the valve open during
operation.
Stop valve tightening torques
Type R(Y)(P)71
Type R(Y)(P)100,125
Service port (5)
980~1470 N•cm (100~150 kgf•cm)
Valve cap
(1)
Liquid pipe
3234~1470 N•cm (100~150 kgf.cm)
Gas pipe
5635~4655 N•cm
(575~475 kgf.cm)
7546~6174 N•cm
(630~770 kgf.cm)
Piping
size
Flare nut
tightening torque
A dimensions for
processing
flares (mm)
Flare shape
Ø 9.5
3270~3990 N•cm
(333~407 kgf•cm)
12.0~12.4
Ø 12.7
4950~6030 N•cm
(504~616 kgf•cm)
15.4~15.8
Ø 15.9
6180~7540 N•cm
(630~770 kgf•cm)
18.6~19.0
Ø 19.1
9720~11860 N•cm
(989.8~1208 kgf•cm)
22.9~23.3
Place
Installation period
Protection method
Outdoor unit
More than a month
Pinch the pipe
Less than a month
Pinch or tape the pipe
Indoor
Regardless of the
period
R=0.4~0.8
45
° ±
2
90
°±
0.5
A
Application of refrigerant oil
(for R407C ether or ester oil should be used)
