Installation and Use
42
GB
CONNECTION PIPING
PIPE UNIONS
LIQUID COCK
GAS COCK
4. Connect the pipes using two spanners, taking care not to damage the
piping. If the tightening force is insuffi cient, then there may well be leaks.
And if the tightening force is excessive, then there may also be leaks as
the fl ange could be damaged. The safest system is constructed by tight-
ening the connection using a fi xed spanner and a dynamometric span-
ner: in this case, use the table "tightening torques for fl ange connections".
5. We recommend you leave an extra 50 cm of pipe for any subsequent
work carried out in the vicinity of the cocks.
2.8 Connections to the external unit
Screw the pipe unions onto the external unit connections with the same
tightness as for the internal unit.
To avoid leaks, pay particular attention to the following points:
- Tighten the pipe unions, taking care not to damage the piping.
- If the tightening force is insuffi cient, then there may well be leaks. And
if the tightening force is excessive, then there may also be leaks as the
fl ange could be damaged.
- The safest system is constructed by tightening the connection using a
dynamometric spanner: in this case, use the tables below (for copper
piping).
TIGHTENING TORQUES FOR FLANGE CONNECTIONS
Pipe Tightening torque
[kgf x cm]
Corresponding e ort
(using a 20 cm spanner)
6.35 mm (1/4”) 160 - 200 wrist force
9.52 mm (3/8”) 300 - 350 arm force
12.70 mm (1/2”) 500 - 550 arm force
15.88 mm (5/8”) 630 - 770 arm force
TIGHTENING TORQUE FOR PROTECTION CAPS
Tightening torque [kgf x cm]
Service connection 70-90
Protection caps 250-300
LENGTH OF THE PIPING
The maximum length for the connection piping varies depending on the
model. When the length is over 5 m, take care to add the right amount of
refrigerant per metre.
If you need to install the external and internal units with a height diff erence
over 5 m (fi g. B and fi g. C), use siphons on the gas piping in order to allow
oil to return to the compressor properly.
NOTE:
We recommend making a loop in the piping near the external unit, so as to
reduce the vibrations transmitted from that point.
IMPORTANT: CHECK FOR REFRIGERANT LEAKS
Once you have created the connections and a vacuum, open the cocks so
that the gas fi lls the piping and always check for leaks using a leak detec-
tor (risk of personal injury from cold burns).
2.9 Creating a vacuum and checking the seal
A vacuum pump suitable for use with R410A must be used to bleed the
circuit.
Make sure the vacuum pump is fi lled with oil to the level indicated by the
oil indicator light, and that the two cocks on the external unit are shut off :
1. unscrew the caps on the cocks of the two-way and three-way valves, and on
the service valve;
max 8 (10) m
5 m
fi g. B
max 8 (10) m
5 m
fi g. C