Daikin VRV IV RKXYQ5T8Y1B Series Installation And Operation Manual page 23

WARNING
Provide adequate measures to prevent that the unit can be
used as a shelter by small animals. Small animals that
make contact with electrical parts can cause malfunctions,
smoke or fire.
14.3 Checking the refrigerant piping
14.3.1 About checking the refrigerant piping
Refrigerant piping works are
finished?
No
Yes
The indoor units, compressor
unit and/or heat exchanger
No
unit were already powered
ON?
Yes
Use procedure:
"Method 2: After power ON".
It is very important that all refrigerant piping work is done before the
units (compressor unit, heat exchanger unit or indoor units) are
powered on.
When the units are powered on, the expansion valves will initialise.
This means that they will close. Leak test and vacuum drying of field
piping, heat exchanger unit and indoor units is impossible when this
happens.
Therefore, there will be explained 2 methods for initial installation,
leak test and vacuum drying.
Method 1: Before power ON
If the system has not yet been powered on, no special action is
required to perform the leak test and the vacuum drying.
Method 2: After power ON
If the system has already been powered on, activate setting [2‑21]
(refer to "To access mode 1 or
expansion valves to guarantee a R410A piping pathway and make it
possible to perform the leak test and the vacuum drying.
NOTICE
Make sure that the heat exchanger unit and all indoor units
connected to the compressor unit are powered on.
NOTICE
Wait until the compressor unit has finished the initialisation
to apply setting [2‑21].
RKXYQ5T8 + RKXYQ8T7Y1B
VRV IV compressor unit for indoor installation
4P499900-1A – 2020.10
a
a
Finish piping work.
Use procedure:
"Method 1: Before power ON
(regular method)".
2" [ 4 30]). This setting will open field
Leak test and vacuum drying
Checking the refrigerant piping involves:
▪ Checking for any leakages in the refrigerant piping.
▪ Performing vacuum drying to remove all moisture, air or nitrogen
in the refrigerant piping.
If there is a possibility of moisture being present in the refrigerant
piping (for example, water may have entered the piping), first carry
a
out the vacuum drying procedure below until all moisture has been
removed.
a
All piping inside the unit has been factory tested for leaks.
Only field installed refrigerant piping needs to be checked.
Therefore, make sure that all the compressor unit stop valves are
firmly closed before performing leak test or vacuum drying.
NOTICE
Make sure that all (field supplied) field piping valves are
OPEN (not compressor unit stop valves!) before you start
leak test and vacuuming.
For more information on the state of the valves, refer to
Setup" [ 4 23].
refrigerant piping:
14.3.2 Checking refrigerant piping: General
guidelines
Connect the vacuum pump through a manifold to the service port of
all stop valves to increase efficiency (refer to
Setup" [ 4 23]).
piping:
NOTICE
Use a 2-stage vacuum pump with a non-return valve or a
solenoid valve that can evacuate to a gauge pressure of
–⁠ 1 00.7 kPa (−⁠ 1 .007 bar)(5 Torr absolute).
NOTICE
Make sure the pump oil does not flow oppositely into the
system while the pump is not working.
NOTICE
Do NOT purge the air with refrigerants. Use a vacuum
pump to evacuate the installation.
14.3.3 Checking refrigerant piping: Setup
The system contains 2 refrigerant circuits:
▪ Circuit 1: Compressor unit → Heat exchanger unit
▪ Circuit 2: Compressor unit → Indoor units
You have to check both circuits (leak test, vacuuming drying). How
to check depends on your available tools:
If you have a
manifold...
With refrigerant line You can check both circuits at once. To do
splitters so, connect the manifold via the splitters to
both circuits, and check.
Without refrigerant You have to check the circuits separately. To
line splitters do so:
(takes twice as long) ▪ First connect the manifold to circuit 1,
▪ Then connect the manifold to circuit 2,
Possible connections:
14 Piping installation
"Checking refrigerant
Then
and check.
and check.
Installation and operation manual
"Checking
23