To Perform Vacuum Drying - Daikin RXYSA4A7V1B Installer And User Manual

To check for leaks after charging refrigerant

18.3.5 To perform vacuum drying

RXYSA4~6A7V/Y1B
VRV 5-S system air conditioner
4P600330-1A – 2020.07
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).
After charging refrigerant in the system an additional leak test must be performed.
Refer to "19.8 To check for refrigerant leaks after
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
information.
To remove all moisture from the system, proceed as follows:
1 Evacuate the system for at least 2 hours to a target vacuum of –⁠ 1 00.7 kPa
(–⁠ 1 .007 bar)(5 Torr absolute).
2 Check that, with the vacuum pump turned off, the target vacuum is
maintained for at least 1 hour.
3 Should you fail to reach the target vacuum within 2 hours or maintain the
vacuum for 1 hour, the system may contain too much moisture. In that case,
break the vacuum by pressurising 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.
4 Depending on whether you want to immediately charge refrigerant through
the refrigerant charge port or first pre-charge a portion of refrigerant through
the liquid line, either open the outdoor unit stop valves, or keep them closed.
See "19.5 To charge
INFORMATION
After opening the stop valve, it is possible that the pressure in the refrigerant piping
does NOT increase. 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.
"18.3.1 About checking the refrigerant piping"
4
refrigerant" [ 97] for more information.
18 Piping installation
|
4
charging" [ 100].
4
[ 88] for more
Installer and user reference guide
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