Daikin RXYQ6BRY16 Installation Manual page 32

NOTICE
The connections to the indoor units and all
indoor units should also be leak and vacuum
tested. Keep any possible (field supplied) field
piping valves open as well.
Refer to the indoor unit installation manual for more
details.
Leak test and vacuum drying should be done
before the power supply is set to the unit. If not, see
also the flow chart earlier described in this chapter
(see "10.4 Leak test and vacuum drying").
NOTICE
The leak test and vacuum drying should be
done using the service ports of gas pipe and
liquid pipe stop valve. See the [R410A]
Indication Label attached to the front panel of
the outdoor unit for details on the location of the
service port (see the figure below).
See 14.3 Method for adding refrigerant for
•
details on handling the stop valve.
The refrigerant charge port is connected to
•
unit pipe. When shipped, the unit contains the
refrigerant, so use caution when attaching the
charge hose.
10.4.5 Leak test
The leak test must satisfy the specifications of EN 378-2:
1 Vacuum leak test:
1.1 Evacuate the system from the liquid and gas piping
to –100.7 kPa (5 Torr) for more than 2 hours.
1.2 Once reached, turn off the vacuum pump and check
that the pressure does not rise for at least 1 hour.
1.3 If the pressure rise, the system may either contain
moisture (see "10.4.6 Vacuum drying") or have leaks.
2 Pressure leak test:
2.1 Break the vacuum by pressurizing with nitrogen
gas to a minimum gauge pressure of 0.2 MPa
(2 bar). Never set the gauge pressure higher than
the maximum operation pressure of the unit,
i.e. 4.0 MPa (40 bar).
2.2 Test for leaks by applying a bubble test solution to
all piping connections or if the pressure does not
drop within 24 hours, the system passes the test.
2.3 Discharge all nitrogen gas.
30
01_EN_3P748230-1.indd 30
[R410A] Indication Label
NOTICE
Make sure to use a recommended bubble test
solution from your wholesaler. Do not use soap
water, which may cause cracking of flare nuts
(soap water may contain salt, which absorbs
moisture that will freeze when the piping gets
cold), and/or lead to corrosion of flared joints
(soap water may contain ammonia which causes
a corrosive effect between the brass flare nut
and the copper flare.
10.4.6 Vacuum drying
To remove all moisture from the system, proceed as
follows:
1
Evacuate the system for at least 2 hours to a target
vacuum of –100.7 kPa.
2
Check that, with the vacuum pump turned off,
the target vacuum is maintained for at least 1 hour.
3
If you fail to reach the target vacuum within 2 hours
or maintain the vacuum for less than 1 hour, the
system may contain too much moisture.
4 In that case, break the vacuum by pressurizing with
nitrogen gas to a gauge pressure of 0.05 MPa
(0.5 bar) and repeat steps 1 to 3 until all moisture
has been removed.
5 The outdoor stop valves can now be opened,
and/or additional refrigerant can be charged
(see "14.3 Method for adding refrigerant").
INFORMATION
After opening the stop valve, it is possible that
the pressure in the refrigerant piping does not
rise. This might be caused by e.g., the closed
state of the expansion valve in the outdoor unit
circuit, but does not present any problem for
correct operation of the unit.
NOTICE
The connections to the indoor units and all
indoor units should also be leak and vacuum
tested. Keep, if existing, all (field supplied) field
valves to the indoor units open as well.
Leak test and vacuum drying should be done
before the power supply is set to the unit. If not,
see "10.4 Leak test and vacuum drying" for
more information.
23/01/2023 17:24:23