Daikin VRV 5-S Series, Инструкция для установки и пользователя

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18 | Piping installation
Installer and user reference guide
90
RXYSA4~6A7V/Y1B
VRV 5-S system air conditioner
4P600330-1 – 2020.01
Valve State of valve
Valve A Open
Valve B Open
Valve C Open
Liquid line stop valve Close
Gas line stop valve Close
NOTICE
Indoor units should also be leak and vacuum tested. Keep any possible (field
supplied) field piping valves open as well.
18.3.4 To perform a leak test
To check for leaks: Vacuum leak test
1 Evacuate the system from the liquid and gas piping to –⁠100.7 kPa (–⁠1.007 bar)
(5 Torr absolute) for more than 2 hours.
2 Once reached, turn off the vacuum pump and check that the pressure does
not rise for at least 1 minute.
3 Should the pressure rise, the system may either contain moisture (see vacuum
drying below) or have leaks.
To check for leaks: Pressure leak test
1 Test for leaks by applying a bubble test solution to all piping connections.
2 Discharge all nitrogen gas.
3 Break the vacuum by pressurising with nitrogen gas to a minimum gauge
pressure of 0.2 MPa (2 bar). Never set the gauge pressure higher than the
maximum working pressure of the unit, i.e. 3.52 MPa (35,2 bar).
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).
To check for leaks after charging refrigerant
After charging refrigerant in the system an additional leak test must be performed.
Refer to
"19.8 To check for refrigerant leaks after charging" [
4
100].
18.3.5 To perform vacuum drying
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
"18.3.1 About checking the refrigerant piping" [ 4 88] for more
information.