Idiomas disponibles
Idiomas disponibles
Maintenance access and
its valve lid
Stop valve lid
Stop valve connection
tube
e
d
a
Sealing component
b
Axis
c
Hexagonal hole
d
Stop valve lid
a
Maintenance access
b
e
c
Using of a stop valve
1. Remove the stop valve lid.
2. Insert the hex wrench into the stop valve, and rotate
the stop valve counter-clockwise.
3. Stop turning when the stop valve cannot be rotated
further.
Result: Valve is now open.
The fastening torque of the stop value is shown in Table
5-2. Insufficient torque may cause the refrigerant to leak.
2
3
1
4
Closing the stop valve
1. Remove the stop valve lid.
2. Insert the hex wrench into the stop valve, and rotate
the stop valve clockwise.
3. Stop turning when the stop valve cannot be rotated
further.
Result: Valve is now closed.
Direction to close:
Fastening torque
Stop valve
size (mm)
Φ12.7
Φ15.9
Φ19.1
Figure 5.23
Φ22.2
Φ25.4
Φ28.6
Φ31.8
Φ35.0
5.5 Flushing Pipes
Figure 5.24
To remove dust, other particles and moisture, which
could cause compressor malfunction if not flushed out
before the system is run, the refrigerant piping should
be flushed using nitrogen. Pipes should be flushed once
the piping connections have been completed except for
the final connections to the indoor units. That is,
flushing should be performed once the outdoor units
have been connected but before the indoor units are
connected.
Only use nitrogen for flushing. Using carbon
dioxide risks leaving condensation in the piping.
Oxygen, air, refrigerant, flammable gases and
toxic gases must not be used for flushing. Use of
such gases may result in fire or explosion.
The liquid and gas sides can be flushed simultaneously;
alternatively, one side can be flushed first and then
Steps 1 to 9 repeated for the other side. The flushing
procedure is as follows:
1.Cover the inlets and outlets of the indoor units to
Figure 5.25
prevent dirt from getting blown in while flushing the pipe.
(Pipe flushing should be carried out before connecting
the indoor units to the piping system.)
2.Attach a pressure reducing valve to a nitrogen cylinder.
3.Connect the pressure reducing valve outlet to the inlet
on the liquid (or gas) side of the outdoor unit.
4.Use blind plugs to block all liquid (gas) side openings,
except for the opening at the indoor unit which is furthest
from the outdoor units ("Indoor unit A" in Figure 5.27).
5.Start to open the nitrogen cylinder valve and gradually
increase the pressure to 0.5Mpa.
6.Allow time for nitrogen to flow as far as the opening at
indoor unit A.
7.Flush the first opening:
a)Using suitable material, such as a bag or cloth, press
firmly against the opening at indoor unit A.
b)When the pressure becomes too high to block with
your hand, suddenly remove your hand allowing the gas
Figure 5.26
to rush out.
c)Repeatedly flush in this manner until no further dirt or
moisture is emitted from the piping. Use a clean cloth to
check for dirt or moisture being emitted. Seal the
opening once it has been flushed.
34
Table 5.2
Tightening torque / N.m
(turn clockwise to close)
Axis
Valve body
9-30
12-30
16-30
24-30
25-35
CAUTION
V.1
