Installation manual
14
RXYSQ6TAV1B
VRV IV-S System air conditioner
4P482260-1 – 2017.03
9.9.
Leak test and vacuum drying
The units were checked for leaks by the manufacturer.
See
and refer to
for nomenclature of the parts in
■
Confirm that the gas and liquid line stop valves are firmly closed
before pressure test or vacuuming.
■
Make sure that valve A is completely open.
Air tight test and vacuum drying
■
Air tight test: Make sure to use nitrogen gas. (For the service
port position, refer to
"9.2. Cautions for handling stop valve" on
.
■
Pressurize the liquid and gas pipes to 4.0 MPa (40 bar) (do not
pressurize more than 4.0 MPa (40 bar)). If the pressure does not
drop within 24 hours, the system passes the test. If the pressure
drops, check where the nitrogen leaks from.
■
Vacuum drying: Use a vacuum pump which can evacuate to
–100.7 kPa (5 Torr, –755 mm Hg)
1.
Evacuate the system from the liquid and gas pipes by using a
vacuum pump for more than 2 hours and bring the system to
–100.7 kPa. After keeping the system under that condition for
more than 1 hour, check if the vacuum gauge rises or not. If it
rises, the system may either contain moisture inside or have
leaks.
2.
Following should be executed if there is a possibility of moisture
remaining inside the pipe (if piping work is carried out during the
raining season or over a long period of time, rainwater may enter
the pipe during work).
After evacuating the system for 2 hours, pressurize the system
to 0.05 MPa (vacuum break) with nitrogen gas and evacuate the
system again using the vacuum pump for 1 hour to –100.7 kPa
(vacuum dr ying). If the system cannot be evacuated to
–100.7 kPa within 2 hours, repeat the operation of vacuum
break and vacuum drying.
Then, after leaving the system in vacuum for 1 hour, confirm that
the vacuum gauge does not rise.
9.10. Additional refrigerant charge
See
for Sky Air or room air conditioner applications or
for VRV applications.
To avoid compressor breakdown. Do not charge the refrigerant
more than the specified amount.
■
This outdoor unit is factory charged with refrigerant and
depending on pipe sizes and pipe lengths some systems require
additional charging of refrigerant. See
additional refrigerant to be charged" on page 12
for Sky Air or
room air conditioner applications or
additional refrigerant to be charged" on page 13
for VRV indoor
units.
■
In case re-charge is required, refer to the nameplate of the unit.
The nameplate states the type of refrigerant and necessary
amount.
Precautions when adding R410A
Be sure to charge the specified amount of refrigerant in liquid state to
the liquid pipe.
Since this refrigerant is a mixed refrigerant, adding it in gas form may
cause the refrigerant composition to change, preventing normal
operation.
■
Before charging, check whether the refrigerant cylinder is
equipped with a siphon tube or not.
■
Refrigerant cannot be charged until field wiring has
been completed.
■
Refrigerant may only be charged after performing the
leak test and the vacuum drying (see above).
■
When charging a system, care shall be taken that its
maximum permissible charge is never exceeded, in
view of the danger of liquid hammer.
■
Charging with an unsuitable substance may cause
explosions and accidents, so always ensure that the
appropriate refrigerant (R410A) is charged.
■
Refrigerant containers shall be opened slowly.
■
Always use protective gloves and protect your eyes
when charging refrigerant.
■
When performing service on the unit requiring the
refrigerant system to be opened, refrigerant must be
evacuated according to local regulations.
■
Do not use the automatic refrigerant charging function
while working on the indoor units.
When using the automatic refrigerant charging
function, the indoor units operate automatically as
well as the outdoor unit.
■
When the power is on, please close the front
panel when leaving the unit.
1
Pressure reducing valve
2
Nitrogen
3
Tank
4
Siphon system
5
Measuring instrument
6
Vacuum pump
7
Valve A
8
Gas line stop valve
9
Outdoor unit
10
Liquid line stop valve
11
Indoor unit
12
Stop valve service port
13
Charge hose
14
BP unit (for Sky Air or room air conditioner indoor units only)
Charge the liquid
refrigerant with the cylinder
in upright position.
Charge the liquid
refrigerant with the cylinder
in up-side-down position.
4PEN482260-1.book Page 14 Monday, March 20, 2017 8:54 PM
